These are the results of the Exchange Server Questionnaire from August 2021.
First of all, I want to thank all of you who participated in the questionnaire. The results are pretty interesting. Even though, that the results are not 100% representative they provide a high-level view of the Exchange Organizations, the mail flow configurations, and the future plans regarding hybrid and Exchange Online.
With 55 replies the questionnaire is far from being a comprehensive representation of the Exchange organizations. But the answers provide an idea of the Exchange landscape used by organizations globally.
Exchange Server 2016 is the dominant version currently in use, followed by Exchange Server 2019. The vast majority of 93% runs modern Exchange Server versions. But there are still older and unsupported Exchange Server versions in use. 7% use Exchange Server 2010 and older.
76% of the organizations maintain up to ten Exchange servers. 20% prefer to rely on just one Exchange server. It is interesting that only 2 (not percent) plan to go hybrid or to move to Exchange Online.
The majority of on-premises Exchange organizations are in the 1,000 - 10,000 mailboxes range. Nevertheless, the SMBs with 1 to 1,000 mailboxes adds up to 50% of the Exchange organizations that took part in this questionnaire. There are just a few organizations that host more than 50,000 mailboxes.
There are Exchange organizations that do not use an SMTP-Gateway solution as part of the mail-flow implementation. Thor organizations that do not use a gateway solution run 1 to 10 Exchange servers on-premises. The majority of those have less than 1,000 mailboxes but there are a few that are responsible for more than 1,000 mailboxes. That leaves the question of why an organization prefers to not secure mal-flow with a gateway.
The use of SMTP gateways is a must, as you do not want to expose your domain member servers to the Internet, not even for the SMTP protocol. A majority of 28 answers for other gateways shows, that there are so many products available and that I did not choose valid answer options upfront.
The Other answers include:
65% of the Exchange organizations of this questionnaire already run in a hybrid configuration with Exchange Online. Only 35% are (still) not using a hybrid setup.
Of those who currently do not run a hybrid configuration only 37% plan on implementing Exchange Hybrid or migrate fully to Exchange Online. Staying on-premises is the only option.
The majority of the organizations still running only an on-premises Exchange organization plan on implementing Exchange Hybrid or migrating to Exchange Online by the end of 2021. None of the participating organizations has plans scheduled after 2022.
It is no surprise that Classic Full Hybrid is the most adopted hybrid configuration. And, no surprise either, none of the other classic hybrid options is implemented. The modern hybrid approach is implemented but with lesser.
The reasons for staying with an on-premises Exchange organization vary. the reasons mentioned are:
There are still organizations that choose an on-premises Exchange organization in favor of Exchange Online. I wonder if company policies for reducing the carbon footprint might drive the migration of on-premises data center resources to hosted cloud services.
Exchange Server vNEXT is in scope for 47% of the organizations. When comparing it with the used Exchange Server version currently in use (~50% Exchange Server 2016) it is an indicator that some companies just skip Exchange Server 2019. Some organizations prefer not to follow the full life-cycle of Exchange Server. s7% of those who do not want to implement Exchange Server vNEXT and want to stay on-premises are single server implementations of Exchange.
The product Exchange Server is still widely used in on-premises deployments. The reasons vary from legal and compliance requirements, network bandwidth constraints, and the overall costs for Exchange Online. Exchange Server vNEXT is a must-have for nearly 50% of the organizations participating in this questionnaire. There are still older and unsupported versions in productive use. Why this is the case is unanswered in this questionnaire.
Organizations running a hybrid Exchange configuration primarily use a Classic Full Hybrid configuration. This might be due to an early implementation in those days when nothing else was available, or due to requirements using Microsoft Teams with on-premises mailboxes. The adoption of Modern Hybrid shows that the Hybrid Agent approach helps organizations that cannot implement a Classic Full Hybrid.
I leave the results of this questionnaire to your interpretation and look forward to your replies, either to this blog post or by social media on Twitter and LinkedIn. Please use the hashtag #ExchangeQuest2021.
There will be a new Exchange Server questionnaire in early 2022, covering various implementation scenarios in more detail. If you want to see a specific Exchange topic covered in the 2022 questionnaire, just let me know.
Again, thank you all for participating in this questionnaire.
You might see the following error in the Windows Application Event Log:
The request failed. Mailbox:
System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send.
---> System.IO.IOException: Unable to read data from the transport connection:
An existing connection was forcibly closed by the remote host.
---> System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult)
at System.Net.Sockets.NetworkStream.EndRead(IAsyncResult asyncResult)
--- End of inner exception stack trace ---
at System.Net.TlsStream.EndWrite(IAsyncResult asyncResult)
at System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar)
--- End of inner exception stack trace ---
at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
The request is successful when you try to connect to the URL provided in the error details using a browser on the Exchange server.
You can verify that the issue by trying to access the URL using the PowerShell Invoke-WebRequest cmdlet. Open a new PowerShell session and try connecting to the URL.
Invoke-WebRequest -Uri $uri
You will receive the same error message as stated in the event log by MSExchangeApplicationLogic. A successful connection returns XML as content.
The reason for this error is related to the .NET Framework TLS configuration, not Exchange Server. The .NET Framework lacks configuration for the use of TLS 1.2.
The solution for this issue is to configure the .NET Framework to correctly use TLS 1.2. You can follow the description for TLS 1.2 enforcement for Azure AD Connect, or you can simply use this Gist.
Due to the changes made to the SCHANNEL configuration you just restart the computer to bring the changes into effect.
Changing the TLS settings does not only affect outgoing connections but incoming connections as well.
Test the TLS changes in a test environment before adjusting your servers in the production environment. If you have not already enabled TLS 1.2 for your Exchange Servers, I recommend reading the 3-part series by the Exchange product group.
Enjoy Exchange Server!
Mail flow from on-premises devices and applications to Exchange Online is a tricky topic. The documentation allows for different solutions.
Recently a client ran into a situation where an on-premises application was not able to deliver messages to a configured inbound connector in the Exchange Online tenant. The connector was configured for remote IP address selection.
Exchange Online responded to each connection attempt with the following error message:
There weren't any changes on the on-premises configuration and the setup was in use for multiple months without any issues.
It took some time to identify the solution, but in the end, the solution was easy.
Disabling and re-enabling solved the issue.
Enjoy Exchange Online.
You might face a situation during an Exchange Server migration where your Exchange Server 2019 mailbox users are not able to open their public folder favorites when using Outlook on the Web (OWA).
When your users try to access a public folder, they receive an error message.
This error occurs when the public folder mailboxes are still hosted on a previous version of Exchange Server. This includes Exchange Server 2016 and 2013.
The online documentation explains, why this is happening:
The solution to this problem is easy. Move the public folder mailboxes to Exchange Server 2019 before you migrate any user mailboxes.
This approach ensures that mailboxes hosted on Exchange Server 2019 and previous versions of Exchange Server are able to access public folders using Outlook on the Web.
Enjoy Exchange Server.
The Microsoft 365 Collaboration BootCamp takes place on 21th & 21st August 2021.
The event addresses collaboration and best practices for using Microsoft Teams, SharePoint, Lists, Groups, and Microsoft Security & Governance.
I am honored to speak about one of my favorite Topics: Microsoft Teams and On-Premises Mailboxes - Troubleshooting 101
Join my session on Saturday 21st August at 12:00 pm (GMT/UTC)