On Saturday, May 11th, the SharePoint Saturday Cologne will take place at Microsoft Office.
My session covers the migration of legacy public folders to modern public folders in the cloud.
Migrating from legacy public folders to modern public folders in Exchange Online is an error-prone process. Especially for Exchange organizations using legacy public folders since the early days. Real world examples from the field will show you how to determine the right migration approach. Additional information will help you to avoid the most common errors when migrating to modern public folders to the cloud. But what about after migrating to the? There is more. Prepare for decommissioning Public Folders by moving content to Microsoft Teams.
See you in Cologne.
Public folders are one solution to provide a team collaboration tool for companies. Legacy public folders utilized a proprietary multi-master replication mechanism which was not planned to handle today's data volumes. Therefore, Exchange 2013 introduced modern public folders which utilize the robust DAG replication functionality. Due to the technology change between legacy public folders and modern public folders a migration is required.
You can migrate legacy public folders hosted on Exchange 2007 or Exchange 2010 to modern public folders hosted on Exchange 2013. Or you can migrate legacy public folders hosted on Exchange 2010 to modern public folders hosted on Exchange 2016. If a cloud migration is a viable option for your company, you are able to migrate legacy public folders hosted on Exchange 2007 or Exchange 2010 to modern public folders hosted in Exchange Online.
The requirements for legacy Exchange Servers are:
Since Exchange Server 2013 RTM the public folder migration scripts and the migration guidance have quite often been updated. The information provided at TechNet is very detailed for each migration option and there is no need to repeat each step in this blog post. Please see the link section for all hyperlinks.
Preparing a legacy public folder migration is pretty straight forward. The main issue companies are facing is the required downtime for finalizing the public folder migration batch. The required downtime cannot be determined exactly (not as exactly as requested by upper management). This means that you have to plan for scheduled maintenance during off-hours. In the past, a single migration request has been used to migrate legacy public folders. The new batch approach migrates public folder content using multiple requests within a single batch.
The Create-PublicFolderMailboxesForMigration.ps1 script uses the parameter EstimatedNumberOfConcurrentUsers to determine the overall number of public folder mailboxes serving the hierarchy. The TechNet articles explain this parameter as follows:
The estimated number of simultaneous user connections browsing a public folder hierarchy is usually less than the total number of users in an organization.
Exchange Server 2013 and Exchange Server 2016 currently support 2.000 concurrent connections to a single mailbox. This limit (2.000) is used by the Create-PublicFolderMailboxesForMigration.ps1 in conjunction with EstimatedNumberOfConcurrentUsers to determine the number of public folder mailboxes required to serve the public folder hierarchy. The current version of the script uses a coded limit of max 100 public folder mailboxes. This means that you can only serve 100 x 2.000 = 200.000 concurrent users accessing the public folder hierarchy.
Finalizing the migration request and setting the PublicFolderMigrationComplete attribute requires the legacy public folder information store to be restarted. Otherwise, the configuration change will not be picked up in the information store in a timely fashion. Remember to restart the information store service on all legacy public folder servers.
If your current public folder infrastructure is based on Exchange 2007 and you want to get rid of that Exchange version, you might think of replicating all content to Exchange 2010. This is not the best approach. Due to known content conversion issues, you might encounter data loss when replicating public folder content between Exchange 2007 and Exchange 2010.
The recommended approach is to migrate Exchange 2007 legacy public folders to Exchange 2013 modern public folders directly.
A recommended reading on legacy public folder migration from Exchange 2010 to Exchange 2016 is Butch Waller’s blog post “Migration to Modern Public Folders – Notes from the Field”
The PowerShell script referenced in that blog post does not work with Exchange 2007. You can use my PowerShell script which utilizes UTF8 encoding and runs with Exchange 2007 and Exchange 2010: https://gallery.technet.microsoft.com/Exchange-2010-Public-315ea9aa
Remark All limits mentioned in this post reflect the information available at the time of writing.
Do you need assistance with your Exchange Server setup? You have questions about your Exchange Server infrastructure and going hybrid with Office 365? Contact us at office365@granikos.eu or visit our website https://www.granikos.eu.
When you want to migrate your legacy public folders from Exchange 2010 to modern public folders in Exchange Online you must prepare the public folder names for migration.
Public folder names are not allowd to contain the following:
The script Fix-PublicFolderNames.ps1 fixes the public folder names in preparation for migration to modern public folders.
# EXAMPLE # Rename and trim public folders found on Server MYPFSERVER .\Fix-PublicFolderNames -PublicFolderServer MYPFSERVER
Migrating legacy public folders (Exchange Server 2010 or older) to modern public folders (Exchange 2013 or newer / Office 365) requires a cleanup of public folders.
There are quite a lot of blog posts and tutorials available describing the general process of migrating legacy public folders to modern public folders.
First you have to identify all public folders having a backslash "\" as part of the public folder name.
Get-PublicFolderDatabase | ForEach {Get-PublicFolderStatistics -Server $_.Server | Where {$_.Name -like "*\*"}}
Just rename those public folders to a name without a backslash.
Another issue might prevent a successful public folder migration: Access Controll Lists (ACL)
This will be the case in public folder hierarchies that go back to the early days of Exchange and have never cleaned up properly during past Exchange migrations.
The cleanup any orphaned Active Directory accounts, run the following PowerShell script.
Get-PublicFolder "\" -Recurse -ResultSize Unlimited | Get-PublicFolderClientPermission | ?{$_.User -like "NT User:S-1-*"} | %{Remove-PublicFolderClientPermission -Identity $_.Identity -User $_.User -Access $_.AccessRights -Confirm:$false}
To cleanup just a single public folder, run the following PowerShell script.
Get-PublicFolder "\My Folder" -Recurse -ResultSize Unlimited | Get-PublicFolderClientPermission | ?{$_.User -like "NT User:S-1-*"} | %{Remove-PublicFolderClientPermission -Identity $_.Identity -User $_.User -Access $_.AccessRights -Confirm:$false}
It should be noted that most of the tutorials have been written using an Exchange Server lab environment with just a few legacy public folders. Therefore, some readers tend to beleive that you only need one modern public folder mailbox. That is not true. In a large legacy public folder infrastructure you will end up with a multiple public folder mailboxes. And the number of mailboxes required to serve the public folder hierarchy.
A larger public folder migration batch using 66 public folder mailboxes looks like this:
Get-MigrationUser -BatchID PFMigration | Get-MigrationUserStatistics | ft -AutoSize Identity Batch Status Items Synced Items Skipped -------- ----- ------ ------------ ------------- PFMailbox1 PFMigration Synced 91993 16 PFMailbox2 PFMigration Synced 103239 0 PFMailbox46 PFMigration Synced 35034 0 PFMailbox56 PFMigration Synced 22554 0 PFMailbox57 PFMigration Synced 20740 0 PFMailbox58 PFMigration Synced 20122 0 PFMailbox59 PFMigration Synced 7209 0 PFMailbox60 PFMigration Synced 104727 0 PFMailbox61 PFMigration Synced 23278 0 PFMailbox62 PFMigration Synced 9760 0 PFMailbox63 PFMigration Synced 9277 0 PFMailbox65 PFMigration Synced 5870 0 PFMailbox64 PFMigration Synced 5639 0 PFMailbox66 PFMigration Synced 21261 0 PFMailbox50 PFMigration Synced 27889 0 PFMailbox52 PFMigration Synced 14063 0 PFMailbox47 PFMigration Synced 29476 0 PFMailbox54 PFMigration Synced 24283 0 PFMailbox55 PFMigration Synced 4646 0 PFMailbox51 PFMigration Synced 59943 0 PFMailbox53 PFMigration Synced 30052 0 PFMailbox49 PFMigration Synced 22746 0 PFMailbox48 PFMigration Synced 16941 0 PFMailbox18 PFMigration Synced 34307 0 PFMailbox19 PFMigration Synced 4523 0 PFMailbox11 PFMigration Synced 100409 0 PFMailbox6 PFMigration Synced 116655 0 PFMailbox4 PFMigration Synced 55240 5 PFMailbox12 PFMigration Synced 37790 0 PFMailbox3 PFMigration Synced 113842 2 PFMailbox22 PFMigration Synced 46416 0 PFMailbox23 PFMigration Synced 37387 0 PFMailbox13 PFMigration Synced 231845 1 PFMailbox7 PFMigration Synced 82859 0 PFMailbox20 PFMigration Synced 65818 0 PFMailbox21 PFMigration Synced 32270 0 PFMailbox9 PFMigration Synced 46609 0 PFMailbox14 PFMigration Synced 30637 0 PFMailbox38 PFMigration Synced 246428 1 PFMailbox43 PFMigration Synced 101837 0 PFMailbox45 PFMigration Synced 157571 0 PFMailbox44 PFMigration Synced 61763 0 PFMailbox40 PFMigration Synced 70637 1 PFMailbox41 PFMigration Synced 143042 0 PFMailbox42 PFMigration Synced 81254 0 PFMailbox39 PFMigration Synced 68876 2 PFMailbox15 PFMigration Synced 58221 0 PFMailbox27 PFMigration Synced 28065 0 PFMailbox24 PFMigration Synced 31869 1 PFMailbox5 PFMigration Synced 64125 0 PFMailbox30 PFMigration Synced 72938 1 PFMailbox33 PFMigration Synced 32545 1 PFMailbox31 PFMigration Synced 93782 0 PFMailbox32 PFMigration Synced 28743 0 PFMailbox25 PFMigration Synced 100794 0 PFMailbox26 PFMigration Synced 35412 0 PFMailbox28 PFMigration Synced 27003 0 PFMailbox29 PFMigration Synced 80510 0 PFMailbox17 PFMigration Synced 97952 1 PFMailbox8 PFMigration Synced 18601 0 PFMailbox34 PFMigration Synced 87150 0 PFMailbox35 PFMigration Synced 31531 0 PFMailbox36 PFMigration Synced 37979 0 PFMailbox37 PFMigration Synced 95770 0 PFMailbox10 PFMigration Synced 14193 0 PFMailbox16 PFMigration Synced 64323 1
Enjoy (modern) public folders.
You need assistance with your Exchange Server setup? You have questions about your Exchange Server infrastructure and going hybrid with Office 365? Contact us at office365@granikos.eu or visit our website https://www.granikos.eu.
When you run your Exchange Organization in hybrid mode with Office 365 and you migrate your on-premise Public Folders to Office 365, you are required to configure a remote Public Folder Mailbox in the Exchange Organization settings.
With Public Folders on-premise your Exchange Online Org looks like this:
Get-OrganizationConfig | fl *public* DefaultPublicFolderAgeLimit : DefaultPublicFolderIssueWarningQuota : 1.7 GB (1,825,361,920 bytes) DefaultPublicFolderProhibitPostQuota : 2 GB (2,147,483,648 bytes) DefaultPublicFolderMaxItemSize : Unlimited DefaultPublicFolderDeletedItemRetention : 30.00:00:00 DefaultPublicFolderMovedItemRetention : 7.00:00:00 PublicFoldersLockedForMigration : False PublicFolderMigrationComplete : False PublicFoldersEnabled : Remote PublicComputersDetectionEnabled : False RootPublicFolderMailbox : 00000000-0000-0000-0000-000000000000 RemotePublicFolderMailboxes : {PublicFolder-Mailbox001}
With Public Folders on-premise your On-Premise Exchange Org looks like this:
Get-OrganizationConfig | fl *public* DefaultPublicFolderAgeLimit : DefaultPublicFolderIssueWarningQuota : Unlimited DefaultPublicFolderProhibitPostQuota : Unlimited DefaultPublicFolderMaxItemSize : Unlimited DefaultPublicFolderDeletedItemRetention : 30.00:00:00 DefaultPublicFolderMovedItemRetention : 7.00:00:00 PublicFoldersLockedForMigration : True PublicFolderMigrationComplete : True PublicFoldersEnabled : Local PublicComputersDetectionEnabled : False RootPublicFolderMailbox : ae0ef819-90d2-45d0-92b6-8b2062cf71a3 RemotePublicFolderMailboxes : {}
With Public Folders in Exchange Online your Exchange Online Org looks like this:
Get-OrganizationConfig | fl *public* DefaultPublicFolderAgeLimit : DefaultPublicFolderIssueWarningQuota : 1.7 GB (1,825,361,920 bytes) DefaultPublicFolderProhibitPostQuota : 2 GB (2,147,483,648 bytes) DefaultPublicFolderMaxItemSize : Unlimited DefaultPublicFolderDeletedItemRetention : 30.00:00:00 DefaultPublicFolderMovedItemRetention : 7.00:00:00 PublicFoldersLockedForMigration : False PublicFolderMigrationComplete : False PublicFoldersEnabled : Local PublicComputersDetectionEnabled : False RootPublicFolderMailbox : 5810bb30-cdda-4287-85a4-8a2547bb9b01 RemotePublicFolderMailboxes : {}
With Public Folders in Exchange Online your Exchange On-Premise Org looks like this:
Get-OrganizationConfig | fl *public* DefaultPublicFolderAgeLimit : DefaultPublicFolderIssueWarningQuota : Unlimited DefaultPublicFolderProhibitPostQuota : Unlimited DefaultPublicFolderMaxItemSize : Unlimited DefaultPublicFolderDeletedItemRetention : 30.00:00:00 DefaultPublicFolderMovedItemRetention : 7.00:00:00 PublicFoldersLockedForMigration : True PublicFolderMigrationComplete : True PublicFoldersEnabled : Remote PublicComputersDetectionEnabled : False RootPublicFolderMailbox : 00000000-0000-0000-0000-000000000000 RemotePublicFolderMailboxes : {mcsmemail.de/Users/PF365-Mailbox-01-55e3d544-ed5a-4557-9008-d8c1b6f06d86}
The remote public folder mailbox has been added to the on-premise Exchange confguration by using:
Set-OrganizationConfig -RemotePublicFolderMailboxes PF365-Mailbox-001 -PublicFoldersEnabled Remote
To be able to add the remote public folder mailbox in a hybrid configuration you are required to add the public folder mailbox (or mailboxes, if you have more than one serving the hierarchy) as a mail user.
Microsoft provides a PowerShell script as part of a script collection here.
When you run the Import-PublicFolderMailboxes.ps1 script you might run into the following error:
Cannot bind parameter 'Name' to the target. Exception setting "Name": "The length of the property is too long. The maximum length is 64 and the length of the value provided is 65." + CategoryInfo : WriteError: (:) [New-MailUser], ParameterBindingException + FullyQualifiedErrorId : ParameterBindingFailed,Microsoft.Exchange.Management.RecipientTasks.NewMailUser + PSComputerName : ex2013.mcsmemail.de
The name attribute for a mail user is limited to 64 characters. But why are you exceeding the length when the mailbox name is only 17 characters long?
It turns out that the PowerSheel script adds a prefix name "" and ther mailbox GUID as a suffix. And voilá, the name exceeds the allowed length for the mail user name attribute.
Don't use more than 16 characters when naming the Public Folder mailboxes in Office 365.
Or modify the Import-PublicFolderMailboxes.ps1 script to fit your needs.
$hasPublicFolderServingHierarchy = $true; $displayName = $publicFolderMailbox.Name.ToString().Trim(); # ORIG: $name = "RemotePfMbx-" + $displayName + "-" + [guid]::NewGuid(); $name = $displayName + "-" + [guid]::NewGuid(); $externalEmailAddress = $publicFolderMailbox.PrimarySmtpAddress.ToString();
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
When you want to migrate your modern public folders from Exchange 2013 or newer to modern public folders in Exchange Online, you must prepare the public folder names for migration.
Public folder names are not allowed to contain the following:
The script Fix-ModernPublicFolderNames.ps1 fixes the public folder names to prepare migration to modern public folders in Exchange Online.
# EXAMPLE 1 # Rename and trim public folders .\Fix-ModernPublicFolderNames.ps1 # EXAMPLE 2 # Rename and trim public folders, export list of renamed # folders and folders with renaming errors as text files .\Fix-ModernPublicFolderNames.ps1 -ExportFolderNames
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On May 11th, the SharePoint Saturday Cologne took place at the new Microsoft Office in Cologne.
My session covered the migration of legacy public folders from Exchange Server 2010 to modern public folders hosted on-premises or Exchange Online. Additionally, I've talked about the pros and cons of a migration to Office 365 Groups and Microsoft Teams.
The slide deck is available on SlideShare.
Enjoy Exchange Server and do not forget about the end of support for Exchange Server 2010 on January 14th, 2010.