Just can't get enough of IT

Once upon a time at an Exchange Conference near you, a member of the Exchange Product Group (PG) announced that the very last Exchange Server will go away when having an active Exchange hybrid setup.

This was a hot topic for discussions at the Microsoft Exchange Conferences (MEC, @IamMEC) in 2012 and 2014, already. Since then the Exchange PG came up with a number of reasons why this is not possible. The question on when we will finally be able to remove the very last Exchange Server from the on-premises Exchange organization was asked every year at the Ignite Conference. 

Current Situation

Currently, the supported scenario for hybrid configurations between your on-premises Exchange organization and Exchange Online requires that you keep the last Exchange Server for creating, and managing Exchange related objects, even if those objects are located in Exchange Online. 

The following diagram illustrates the current requirements:

• Domain Controller Servers, with the most recent Active Directory Schema Update for a supported Exchange Server version, and stored Exchange-extended AD objects.
• DirSync Server, with AAD Connect, synchronizing Exchange-extended AD objects stored in on-premises Active Directory with Azure AD.
• Last Exchange Server, running a supported version of Exchange Server, managing the objects stored in on-premises Active Directory.

Interim solutions

In the past, there was communication on certain interim solutions that were supposed to support you in removing the last Exchange Server from your Exchange organization. Such interim solutions were:

• ADSI Edit
• Identity Management Solutions (IDM)
• PowerShell

At Ignite those solutions even made it into the official session catalog:

• Ignite 2018 - THR2145 - Why do we need to keep an Exchange Server on-premises when we move to the cloud?

All those interim solutions leave your on-premises Exchange organization and the Active Directory configuration in an uncomfortable twilight-zone. It was still something that worked somehow, but you knew it was officially not supported, and the secure and stable operation of the hybrid configuration was at risk.

But wait...

Removing the last Exchange Server is supported!

(at least when all components are released)

Solution

The new approach for managing your Exchange Online tenancy after migrating your on-premises Exchange organization to Exchange Online does not require an on-premises Exchange Server. 

The new mode of operation reduces your on-premises requirements to:

• Domain Controller Servers, running the most recent release Windows Server 2019 with the most recent Active Directory Schema Update for Exchange Server 2019 CU 5. This updates the Exchange-extended AD objects and the hybrid configuration object to support modern EXO management. Also, you must enable the Windows Feature "Exchange Online Remote Features" as described below.
   
• DirSync Server, with AAD Connect, synchronizing Exchange-extended AD objects stored in on-premises Active Directory with Azure AD. You must run the most recent release of Azure AD Connect (1.4.38.0) and have Exchange Hybrid enabled in AAD Connect.
  See release notes for Azure AD Connect. 
   
• Administrative PC, running the most recent version of the Exchange Online PowerShell v2 (aka ExchangeOnlineManagement)

The following diagram illustrates the new modern Exchange Online Management experience:

Simply you remove the requirement to use on-premises Exchange Server to write to your on-premises Active Directory. Instead, Azure AD Connect uses a new synchronization capability to handle the new Exchange Management experience in the AAD Connect MetaVerse. The on-premises AD-connector writes the changes to Active Directory which keeps the Active Directory up-to-date for all other on-premises solutions that require identities to have a proper state.

You execute all Exchange-related actions using the new Exchange Online Management PowerShell module, or, if needed, the new Modern Exchange Admin Center (EAC, which was announced at Ignite 2019.

Enable Modern Exchange Admin Experience (MEAE)

Before you uninstall the last Exchange Server from your on-premises Exchange organization, ensure that you

• Updated the Active Directory Schema Version to Exchange Server 2019 CU5
• Prepare the Active Directory and all domains in the Active Directory Forest that contain Exchange objects
• Ensure that there are not pre-Windows 2019 domain controller in use, and patch all domain controller to the March 2020 release
• Install the new EXORemote Windows Feature 

PS C:\> Get-WindowsFeature

Display Name                                            Name                       Install State
------------                                            ----                       -------------
[ ] Active Directory Certificate Services               AD-Certificate                 Available
    [ ] Certification Authority                         ADCS-Cert-Authority            Available
    [ ] Certificate Enrollment Policy Web Service       ADCS-Enroll-Web-Pol            Available
    [ ] Certificate Enrollment Web Service              ADCS-Enroll-Web-Svc            Available
    [ ] Certification Authority Web Enrollment          ADCS-Web-Enrollment            Available
    [ ] Network Device Enrollment Service               ADCS-Device-Enrollment         Available
    [ ] Online Responder                                ADCS-Online-Cert               Available
[ ] Active Directory Domain Services                    AD-Domain-Services             Available
[ ] Active Directory Federation Services                ADFS-Federation                Available
[ ] Active Directory Lightweight Directory Services     ADLDS                          Available
[ ] Active Directory Rights Management Services         ADRMS                          Available
    [ ] Active Directory Rights Management Server       ADRMS-Server                   Available
    [ ] Identity Federation Support                     ADRMS-Identity                 Available
[ ] Device Health Attestation                           DeviceHealthAttestat...        Available
[ ] DHCP Server                                         DHCP                           Available
[ ] DNS Server                                          DNS                            Available
[ ] Exchange Online Remote Features                     EXORemote                      Available
[ ] Fax Server                                          Fax                            Available
[X] File and Storage Services                           FileAndStorage-Services        Installed
    [X] File and iSCSI Services                         File-Services                  Installed
        [X] File Server                                 FS-FileServer                  Installed
        [ ] BranchCache for Network Files               FS-BranchCache                 Available
[...]

PS C:\> Install-WindowsFeature -Name EXORemote

Display Name                                            Name                       Install State
------------                                            ----                       -------------
[ ] Active Directory Certificate Services               AD-Certificate                 Available
    [ ] Certification Authority                         ADCS-Cert-Authority            Available
    [ ] Certificate Enrollment Policy Web Service       ADCS-Enroll-Web-Pol            Available
    [ ] Certificate Enrollment Web Service              ADCS-Enroll-Web-Svc            Available
    [ ] Certification Authority Web Enrollment          ADCS-Web-Enrollment            Available
    [ ] Network Device Enrollment Service               ADCS-Device-Enrollment         Available
    [ ] Online Responder                                ADCS-Online-Cert               Available
[ ] Active Directory Domain Services                    AD-Domain-Services             Available
[ ] Active Directory Federation Services                ADFS-Federation                Available
[ ] Active Directory Lightweight Directory Services     ADLDS                          Available
[ ] Active Directory Rights Management Services         ADRMS                          Available
    [ ] Active Directory Rights Management Server       ADRMS-Server                   Available
    [ ] Identity Federation Support                     ADRMS-Identity                 Available
[ ] Device Health Attestation                           DeviceHealthAttestat...        Available
[ ] DHCP Server                                         DHCP                           Available
[ ] DNS Server                                          DNS                            Available
[X] Exchange Online Remote Features                     EXORemote                      Installed
[ ] Fax Server                                          Fax                            Available
[X] File and Storage Services                           FileAndStorage-Services        Installed
    [X] File and iSCSI Services                         File-Services                  Installed
        [X] File Server                                 FS-FileServer                  Installed
        [ ] BranchCache for Network Files               FS-BranchCache                 Available
[...]

Even though not explicitly stated, you should restart the server after installing the Windows feature.

• Connect to the modern Exchange Online Admin Center as a Global Administrator or Exchange Services Administrator and add at least one of your on-premises domain controllers to the list of modern management servers.
  https://admin.exchange.microsoft.com/#/modernmanagement

As part of the next AAD Connect synchronization cycle, the magic happens.

• The added EXO modern management server is validated
  • You'll see an error sign in Modern Exchange Admin Center if the validation has failed
•  Azure AD removes the "on-premises"-lock from the Exchange related attributes, so you can start managing these attributes in EXO
• The Exchange hybrid configuration object is set to "Modern Coexistence", ensuring that a newly added on-premises Exchange Server will not interfere with the setup

Verify that you can edit the Exchange related attributes of synchronized Active Directory objects in Exchange Online or Azure AD before you remove your last Exchange Server. 

Whey ready to uninstall the last Exchange Server you must use the following command line parameters to remove the server as intended. Otherwise, you'll leave the Exchange organization in an inchoate state. Ensure that you use an administrative PowerShell session. 

./Setup.exe /mode:uninstall /SwitchToMEMA /IAcceptExchangeOnlineLicenseTerms

Normally, you do not have to accept license terms when uninstalling Exchange Server, but in this case, you have to accept the Exchange Online license terms.

Prerequisites

• Windows Server 2019 Desktop Experience Editon or Core Edition, March 2020 Update
  Core Edition recommended
• Azure AD Connect, release 1.4.38.0
• Exchange Server 2019 CU5, as the last Exchange Server

Links

• Exchange Online Management PowerShell Module v2
• Hybrid deployment prerequisites
• Exchange Server hybrid deployments
• Install-WindowsFeature
• You must follow the instructions given in the follow article:
  Final instructions for enabling this awesome new MEMA-experience

Enjoy the modern experience and management options of Exchange Online!

Exchange Conferences

• MEC 2014 - Austin
• MEC 2012 - Orlando

Problem

You are not able to list public folders in a co-existence scenario with Exchange Server 2007 and Exchange Server 2010/2013 using the Exchange 2007 EMS or EMC.

When you try to execute Get-PublicFolder you receive the following error:

Get-PublicFolder " There is no existing PublicFolder that matches the following Identity: '\'. Please make sure that you specified the correct PublicFolder Identity and that you have the necessary permissions to view PublicFolder.

This might happen after you have removed the first Exchange 2007 mailbox server, but not the last Exchange 2007 mailbox server.

Exchange Server 2007 uses the Exchange System Attendant to access the public folder store and fails if the System Attendant discovery in Active Directory does not provide a proper configuration.

KB 2621350 describes the discovery process:

1. Exchange Server 2007 selects a mailbox database.
2. Exchange Server 2007 obtains the LegacyExchangeDN attribute of the selected mailbox database. For example, Exchange Server 2007 obtains the following LegacyExchangeDN attribute value:
   /o=First Organization/ou=Exchange Administrative Group (group_name)/cn=Configuration/cn=Servers/cn=E14HUBCAS/cn=Microsoft Private MDB
3. Exchange Server 2007 removes the "CN=Mailbox Database" part of the address. The address then resembles the following:
   /o=First Organization/ou=Exchange Administrative Group (group_name)/cn=Configuration/cn=Servers/cn=E14HUBCAS
4. Exchange Server 2007 adds "CN=Microsoft System Attendant" to the LegacyExchangeDN value. After the value is appended, the LegacyExchangeDN attribute value resembles the following:
   /o=First Organization/ou=Exchange Administrative Group (group_name)/cn=Configuration/cn=Servers/cn=E14HUBCAS/CN=Microsoft System Attendant
5. Exchange Server 2007 tries to log on to the public store by using the value in step 4.
6. The store then tries to locate the System Attendant object.

There two annoying things about these steps

1. Step 1:  Exchange Server 2007 selects a mailbox database
   
   There is no description available on how the database is being selected. But the co-existence scenario results in a mailbox database being selected that might be located on Exchange Server 2010 or Exchange Server 2013. Even though there still are Exchange Server 2007 mailbox database available. You still require to have a mailbox database hosted on an Exchange 2007 public folder server, due to the legacy public folder requirements with Exchange Server 2013.
    
2. Steps 2-4: The LegacyExchangeDN example shows an E14HUBCAS name as a placeholder. In a situation where you have deployed dedicated mailbox servers, this should read E14MBX.
    

Solution

The magic System Attendant mailbox has been removed from Exchange 2010. But the System Attendent configuration node does still exist in the Active Directory Configuration Partition for compatibility reasons. The configured attributes of the System Attendant entry vary depending on the version of the installed Exchange Server.

In regards to the public folder issue, we need to focus on the following:

• Exchange Server 2010 System Attendant
  • homeMDB: <not set>
  • homeMTA: <not set>
• Exchange Server 2013 System Attendant
  • homeMDB: <not set>
  • homeMTA: CN=Microsoft MTA,CN=E15MBX,CN=Servers,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=[ORG],CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=[DOMAIN],DC=[TLD]

To fix the public folder access issue for Exchange Server 2007, set the homeMDB and homeMTA attributes. Set the Exchange System Attendant attributes to appropriate values for your Exchange servers.

Exchange Server 2013

1. Open ADSIEdit and connect to the Configuration context
2. Open Databases node
   CN=Databases,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=[ORG],CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=[DOMAIN],DC=[TLD]
3. Open the Properties of an Exchange 2013 database
4. View the distinguishedName property and copy the value to clipboard
   Example: CN=E15MBXDB01,CN=Databases,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=[ORG],CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=[DOMAIN],DC=[TLD]
5. Close the Properties window and open the Servers node
   CN=Servers,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=[ORG],CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=[DOMAIN],DC=[TLD]
6. Expand the first Exchange 2013 server and open the Properties of the Microsoft System Attendant node
   Ensure that the view is not filtered to Show only attributes that have values
7. Edit the homeMDB attribute and paste the distinguished name of the mailbox database copied in step 4
8. Apply the changes and close the properties window

Repeat steps 4 to 8 for each Exchange 2013 server in your environment.

Exchange Server 2010

1. Open ADSIEdit and connect to the Configuration context
2. Open Databases node
   CN=Databases,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=[ORG],CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=[DOMAIN],DC=[TLD]
3. Open the Properties of an Exchange 2010 database
4. View the distinguishedName property and copy the value to the clipboard
   Example: CN=E14MBXDB01,CN=Databases,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=[ORG],CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=[DOMAIN],DC=[TLD]
5. Close the Properties window and open the Servers node
   CN=Servers,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=[ORG],CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=[DOMAIN],DC=[TLD]
6. Expand the first Exchange 2010 server and open the Properties of the Microsoft System Attendant node
   Ensure that the view is not filtered to Show only attributes that have values
7. Edit the homeMDB attribute and paste the distinguished name of the mailbox database copied in step 4
8. Apply the changes and close the properties window
9. Open the Properties windows of the Microsoft MTA of the same Exchange
10. View the distinguishedName property and copy the value to the clipboard
    Example: CN=Microsoft MTA,CN=E14MBXSRV01,CN=Servers,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=[ORG],CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=[DOMAIN],DC=[TLD]
11. Open the properties of the Microsoft System Attendant node for a second modification
    Ensure that the view is not filtered to Show only attributes that have values
12. Edit the homeMTA attribute and paste the distinguished name of the mailbox database copied in step 10
13. Apply the changes and close the properties window

Repeat steps 4 to 13 for each Exchange 2010 server in your environment.

Wait for Active Directory replication and retry to access the public folders using Get-PublicFolder in an Exchange Server 2007 Management Shell.

It might be required to restart the Exchange 2007 Information Store and System Attendant service of the Exchange 2007 server in question

Use an administrative PowerShell

Restart-Service MSExchangeIS 
Restart-Service MSExchangeSA 

I haven’t noticed any issues in production environments so far. If you encounter any issues in your environment, feel free to leave a comment.

Links

• You cannot view a list of public folders in an Exchange organization that has Exchange Server 2007 and Exchange Server 2010 mailbox databases,
• On-Premises Legacy Public Folder Coexistence for Exchange 2013 Cumulative Update 7 and Beyond,
• Breaking Change : The System Attendant mailbox has been removed from Exchange 2010
• Exchange 2007 and 2013 environment – Public Folders on 2007 “Get-PublicFolder” cmdlet fails

Do you need assistance with your Exchange Server setup? You have questions about your Exchange Server infrastructure and going hybrid? You are interested in what Exchange Server 2016 has to offer for your environment?

Contact me at thomas@mcsmemail.de
Follow at https://twitter.com/stensitzki

Description

This script reads Exchange Organization data and creates a single Microsoft Word document. A later version will support exporting to an Html file.

The script requires an Exchange Management Shell for Exchange Server 2016 or newer. Older EMS versions are not tested.

A locally installed version of Word is required, as plain Html export is not available, yet.

The default file name is 'Exchange-Org-Report [TIMESTAMP].docx'. 

Most of the script requires only Exchange admin read-only access for the Exchange organization. Querying address list information requires a membership in the RBAC role "Address Lists".

The script queries hardware information from the Exchange server systems and requires local administrator access to the computer systems.

Examples

# Example 1
# Create a Word report for the local Exchange Organization using 
# the default values defined on the parameters section of the PowerShell script.

.\Get-ExchangeOrganizationReport.ps1 -ViewEntireForest:$true

# Example 2
# Create a Microsoft Word report for the local Exchange Organization with 
# a verbose output to the current PowerShell session.

.\Get-ExchangeOrganizationReport.ps1 -Verbose

Version History

• 0.9. Initial community release
• 0.91, Information about processor cores, memory, and page file size added

Links

• Download and follow at Github: https://github.com/Apoc70/Get-ExchangeOrganizationReport
• Download and like at TechNet Gallery: https://gallery.technet.microsoft.com/Gather-Exchange-Organizatio-8c0dd625

Additional Credits

The script is based on the ADDS_Inventory.ps1 PowerScript by Carl Webster: https://github.com/CarlWebster/ActiveDirectory

Follow

• Twitter @stensitzki
• LinkedIn
• Xing

Last Updated: 2018-07-06

Description

This scripts creates a new room mailbox and security two groups for full mailbox access and and for send-as delegation. The security groups are created using a configurable naming convention. If required by your Active Directory team, you can add group prefixes or department abbreviations as well.

The script uses a Xml configuration file to simplify changes for variables unique for your environment.

High level steps executes by the script:

1. Create a new room mailbox
2. Create a new mail enabled security group for full access delegation
3. Assign full access security group for full access to the room mailbox
4. Create a new mail enabled security group for send-as delegation
5. Assign send-as permissions to send-as security group
6. Create a new mail enabled security group for allowed user to book the new room mailbox
7. Set calendar processing to AutoAccept, if required
8. Set resource capacity, if rewuired

Examples

Xml settings file

Note

The calendar booking security group feature is currently not available. But will be available in an upcoming release.

The following example creates a room mailbox for an Conference Room with empty security groups.

.\New-RoomMailbox.ps1 
  -RoomMailboxName "MB - Conference Room" 
  -RoomMailboxDisplayName "Board Conference Room" 
  -RoomMailboxAlias "MB-ConferenceRoom" 
  -RoomMailboxSmtpAddress "ConferenceRoom@mcsmemail.de" 
  -DepartmentPrefix "C"

You can simplify the use of the script by using a paramterized helper script named Run-NewRoomMailbox.ps1.

The following Run-NewRoomMailbox.ps1 script simplifies the process of creating a team mailbox even more.

$roomMailboxName = 'MB-Conference Room'
$roomMailboxDisplayName = 'Board Conference Room'
$roomMailboxAlias = 'MB-ConferenceRoom'
$roomMailboxSmtpAddress = 'ConferenceRoom@mcsmemail.de'
$departmentPrefix = 'C'
$groupFullAccessMembers = @('JohnDoe','JaneDoe')  # Empty = @()
$groupSendAsMembers = @()
$groupCalendarBookingMembers = @()
$RoomCapacity = 0
$RoomList = 'AllRoomsHQ'
$Language = 'en-GB'


.\New-RoomMailbox.ps1 
  -RoomMailboxName $roomMailboxName 
  -RoomMailboxDisplayName $roomMailboxDisplayName 
  -RoomMailboxAlias $roomMailboxAlias 
  -RoomMailboxSmtpAddress $roomMailboxSmtpAddress 
  -DepartmentPrefix $departmentPrefix 
  -GroupFullAccessMembers $groupFullAccessMembers 
  -GroupSendAsMembers $groupSendAsMembers
  -RoomCapacity $RoomCapacity 
  -AutoAccept 
  -RoomList $RoomList
  -Language $Language

Version History

• 1.0, Initial community release
• 1.1, Some PowerShell hygiene, issue #2 closed
• 1.2, CalenderBooking, Language added

Links

• Download and follow at Github: https://github.com/Apoc70/New-RoomMailbox​
• Download and like at TechNet Gallery: https://gallery.technet.microsoft.com/Create-a-new-Room-Mailbox-99a4e477

Follow

• Twitter @stensitzki
• LinkedIn
• Xing

Problem

I came across an interesting issue when setting up a new Exchange 2013 server in an Exchange organization having the cmdlet extension agent enabled.

As mentioned in my last post Exchange setup checks for the existence of the ScriptingAgentConfig.xml file when agent extenstion is enabled in the Exchange organization. It turned out that this ist not only true when you install an Exchange update using /mode:update, but as well when installing a new Exchange server using /mode:install.

The following error occurs when Exchange Management Tools are provisioned.

Configuring Microsoft Exchange Server

    Preparing Setup                                                               COMPLETED
    Stopping Services                                                             COMPLETED
    Copying Exchange Files                                                        COMPLETED
    Language Files                                                                COMPLETED
    Restoring Services                                                            COMPLETED
    Language Configuration                                                        COMPLETED
    Exchange Management Tools                                                     FAILED
     The following error was generated when "$error.Clear();
          Set-WERRegistryMarkers;
        " was run: "Microsoft.Exchange.Provisioning.ProvisioningBrokerException: Provisioning layer
initialization failed: '"Scripting Agent initialization failed: "File is not found: 'C:\Program File
s\Microsoft\Exchange Server\V15\Bin\CmdletExtensionAgents\ScriptingAgentConfig.xml'.""' ---> Microso
ft.Exchange.Provisioning.ProvisioningException: "Scripting Agent initialization failed: "File is not
 found: 'C:\Program Files\Microsoft\Exchange Server\V15\Bin\CmdletExtensionAgents\ScriptingAgentConf
ig.xml'."" ---> System.IO.FileNotFoundException: "File is not found: 'C:\Program Files\Microsoft\Exc
hange Server\V15\Bin\CmdletExtensionAgents\ScriptingAgentConfig.xml'."
   at Microsoft.Exchange.ProvisioningAgent.ScriptingAgentConfiguration.Initialize(String xmlConfigPa
th)
   at Microsoft.Exchange.ProvisioningAgent.ScriptingAgentConfiguration..ctor(String xmlConfigPath)
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.ProvisioningAgent.ScriptingAgentConfiguration..ctor(String xmlConfigPath)
   at Microsoft.Exchange.ProvisioningAgent.ScriptingAgentClassFactory.get_Configuration()
   at Microsoft.Exchange.ProvisioningAgent.ScriptingAgentClassFactory.GetSupportedCmdlets()
   at Microsoft.Exchange.Provisioning.ProvisioningBroker.BuildHandlerLookupTable(CmdletExtensionAgen
t[] enabledAgents, Exception& ex)
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.Provisioning.ProvisioningLayer.GetProvisioningHandlersImpl(Task task)
   at Microsoft.Exchange.Provisioning.ProvisioningLayer.GetProvisioningHandlers(Task task)
   at Microsoft.Exchange.Configuration.Tasks.Task.<BeginProcessing>b__4()
   at Microsoft.Exchange.Configuration.Tasks.Task.InvokeNonRetryableFunc(Action func, Boolean termin
atePipelineIfFailed)".

As expected a fresh Exchange install contains the sample file only. The following screenshot shows the Exchange Management Shell and the releated folder in the background.

Solution

The only solution currently known to me is to disable the cmdlet extension agent until the setup of the new Exchange server has finished.

Disable-CmdletExtensionAgent "Scripting Agent"

Having the cmdlet extension agent disabled the setup finishes without any issues. Don't forget to copy the cmdlet extension Xml file to the newly built server and to enable the cmdlet extension agent again.

Enable-CmdletExtensionAgent "Scripting Agent"

Links

• Cmdlet extension agents

You need assistance with your Exchange Server setup? You have questions about your Exchange Server infrastructure and going hybrid? You are interested in what Exchange Server 2016 has to offer for your environment?

Contact me at thomas@mcsmemail.de
Follow at https://twitter.com/stensitzki

Problem

The use of Exchange Edge Transport Servers requires the synchronization of user and configuration data from internal Exchange Servers to the Edge Transport Servers. The synchronization utilizes secure LDAP (EdgeSync) to transmit the data securely and is based on an Edge Subscription.

When you create a new Edge Subscription on your internal Exchange Servers by importing the Edge Subscription XML-file, establishing the EdgeSync-connection might fail.

You will find the following error in the application event log of the internal Exchange Server:

Log Name:      Application
Source:        MSExchange EdgeSync
Event ID:      1035
Task Category: Synchronization
Level:         Error
Keywords:      Classic
Description:
EdgeSync failed to synchronize because it only supports Cryptographic API certificates. 
The local Hub Transport server's default certificate with thumbprint XYZ isn't a 
CAPI certificate. To set a CAPI certificate as the default certificate, use the 
Enable-ExchangeCertificate cmdlet with the Services parameter using the value of SMTP.

Reason

The private key of the current Exchange Transport default certificate of the internal Exchange servers uses a CNG private key. EdgeSync requires a CAPI1 based private key.

• CNG = Cryptography Next Generation
• CAPI1 = Cryptographic API (already deprecated)

This problem occurs primarily when using an Enterprise Certificate Authority using certificate templates with individual template settings. 

How do you determine, if the type of the default transport certificate is a CNG or CAPI1 certificate?

• Log on to the internal Exchange Server where you imported the Edge Subscription file and start a new Exchange Management Shell session
• Query the Transport Service to identify the default certificate thumbprint

Get-TransportService | ft Name,InternalTransportCertificateThumbprint

• Open an administrative command prompt
• Export the certificates information from the certificate store to a text file

certutil -v -store my > cert.txt

• Open the text file using an editor tool of your choice
• Search for the certificate thumbprint identified in step 2
  This thumbprint is the SHA1 certificate hash
• Scroll down to the provider section to find the following two attributes
  • ProviderType
  • KeySpec

If both attribute are of the value 0, the certificate if a CNG certificate.

The section might look like this:

Unique container name: XYZ
    Provider = Microsoft Software Key Storage Provider
    ProviderType = 0
  Flags = 20 (32)
    CRYPT_MACHINE_KEYSET -- 20 (32)
    KeySpec = 0 -- XCN_AT_NONE

Solution

Use OpenSSL to convert the CNG certificate to a CAPI1 certificate.

Using OpenSSL requires the download of the Windows release of OpenSSL. I recommend to not install the software on the Exchange Server but a separate Windows server or your administrative desktop system. Additionally, you need the certificate with its private key as a PFX-file.

Use the following steps to convert the CNG certificate to a CAPI1 certificate.

• Download and install OpenSSL
• Open the OpenSSL Command Prompt
• Navigate to the folder containing the PFX-file
• Convert the PFX-file to a PEM-file
  The tool will query to enter the PFX password

openssl pkcs12 -in CERT.pfx -out cert.pem -nodes

• Convert the PEM-file to a new PFX-file
  The tool will query you to set a PFX password

openssl pkcs12 -export -in cert.pem -out NEWCERT.pfx

The new PFX-file is now a CAPI1 certificate. The new certificate has the same thumbprint. Now you must replace the current certificate used by Exchange Server with the new certificate. 

Replacing the certificate requires a downtime of each Exchange Server requiring the certificate replacement. This is due to the requirement to remove the CNG certificate first, following the import of the CAPI1 certificate. Afterward, you need to enable the required Exchange services.

• Log on to the internal Exchange Server where you imported the Edge Subscription file and start a new Exchange Management Shell session
• Query local Exchange Server certificates and identify the thumbprint of the default Exchange Server self-signed certificate 
  The certificate common name (CN) equals the server name

Get-ExchangeCertificate -Server SERVERNAME

• Change the Exchange Transport default certificate to the self-signed certificate before deleting the CNG certificate

# It is mandatory to answer the query for replacing the default certificate with YES
Enable-ExchangeCertificate -Thumbprint THUMBPRINT -Services SMTP

# Restart the transport service
Restart-Service MSExchangeTransport

• Remove the CNG certificate
  • Use either the certificate store MMC, Exchange Management Shell, or Exchange Admin Center
• Import the CAPI1 certificate
  • Use either the certificate store MMC, Exchange Management Shell, or Exchange Admin Center
• Enable the imported certificate and replace the default transport certificate

# It is mandatory to answer the query for replacing the default certificate with YES
Enable-ExchangeCertificate -Thumbprint NEWCERTTHUMBPRINT -Services SMTP

# Restart the transport service
Restart-Service MSExchangeTransport

• Repeat the certificate replace for each Exchange Server in the same Active Directory site

Now, that you updated the local Exchange Servers there is one more step that needs to be checked on the Edge Transport Servers.

Edge Transport Servers are not domain-joined and therefore do not receive any GPO-based configuration. Each required configuration must be performed locally. To ensure that the default transport certificate of the internal Exchange servers can be used for cryptographic operations we must ensure that the certificate chain of that certificate is present in the certificate store of Edge Transport servers.

Take a look at the certificate chain of the converted CAPI1 certificate and import the Root-CA and Subordinate-CA certificates into the Edge Transport servers local certificate store. You must ensure that the certificates are placed into appropriate stores:

• Root-CA certificate goes into Trusted Root Certification Authorities \ Certificates
• Subordinate-CA certificate goes into Intermediate Certification Authorities \ Certificates

Next, you create a new Edge Subscription on your Edge Transport server and create a new subscription for the Active Directory site on the internal Exchange Server. The internal Exchange Servers are now able to establish an EdgeSync connection and encrypting the data transferred to the Edge Transport servers.

Note

When you receive the TLS certificate as PFX/PKCS12 file, you import the certificate and the private key. The import process itself defines the priavte key Crypto Provider. Using the following command line you ensure that the import process suses the legacy crypto provider.

certutil -csp "Microsoft RSA SChannel Cryptographic Provider" -importpfx my MYCERTpfx

Links

• Exchange Edge Transport Server Role
• Edge Subscriptions
• Cryptography API: Next Generation
• Cryptographic Service Providers
• OpenSSL for Windows

Enjoy Exchange Server and Edge Transport!

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