Exchange MoveRequest: StalledDueToSource_DiskLatency

During an Exchange 2016 to Exchange 2019 migration, no mailboxes could be moved to the new Exchange 2019 databases. The MoveRequests got stuck at 0% and showed the error StalledDueToSource_DiskLatency: No matter how big or small the mailbox was: No mailbox could be moved. Directly after creating the MoveRequest, the error StalledDueToSource_DiskLatency was displayed. Also ... Read more

Exchange 2019: ExchangeStoreDB EventID 171 database cannot be mounted

Problems can occur on an Exchange 2019 server if a database is larger than 1 TB. On an Exchange 2019 Standard Server, the maximum database size is 1 TB, if the database is larger, there are problems with failover within the DAG. Also, databases that are larger than 1 TB can no longer be ... Read more

Transport-based Enforcement System: Microsoft starts blocking old Exchange servers

In order to continue to guarantee the security of Exchange Online, Microsoft is gradually starting to block old Exchange Server versions. The new system, which is now being introduced gradually, is called the "Transport-based Enforcement System" and has three functions: Reporting, throttling and blocking. In the first stage, administrators are informed that old Exchange Server versions are present in the company. Read more

New security updates for Exchange Server (March 2023)

Microsoft has released new security updates for Exchange Server 2013, 2016 and 2019. This is likely to be the last security update for Exchange 2013, as support for Exchange 2013 ends on 11.04.2023. The March update for Exchange also fixes the problem with the crashing EWS Web Application Pool in IIS. Applications that use EWS should therefore ... Read more

Exchange Server and exclusions for virus scanners

Microsoft has updated the recommendations for exclusions for virus scanners on Exchange Server: Specifically, contrary to the original recommendation, these directories and processes should no longer be excluded from the virus scanner: Existing exclusions for virus scanners should therefore be adjusted. The script from Paul Cunningham, which creates a list of all exclusions, is suitable for new Exchange installations: Unfortunately, ... Read more

Windows Extended Protection and Exchange Server

The "Windows Extended Protection" security feature was introduced with a security update in August 2022 for Exchange Server 2013, 2016 and 2019 and protects against man in the middle (MitM) attacks. In small organizations where there is only a single Exchange Server, without load balancers and web application firewalls, Windows Extended Protection can be activated quite easily. In ... Read more

New security updates for Exchange Server (February 2023)

Microsoft has released new security updates for Exchange 2013, 2016 and 2019. A total of 4 vulnerabilities classified as important have been fixed. Details on the closed vulnerabilities can be found here: As you can see, all 4 vulnerabilities are Remote Code Execution vulnerabilities, so the updates should be installed as soon as possible. Here it goes ... Read more

Exchange Migration: Outlook asks for password

During the migration from Exchange 2016 to Exchange 2019, I encountered the problem that Outlook constantly asks for username and password. A connection via Outlook to Exchange could no longer be established as soon as the DNS entry (or the load balancer) was switched to the new Exchange 2019 servers. However, OWA and ActiveSync worked without any problems. In ... Read more

Microsoft asks for feedback on Exchange updates

Microsoft would like to improve the installation of Cumulative Updates (CUs) and Security Updates (SUs) for Exchange Server and is therefore asking for feedback from administrators in an anonymous online survey. Until the end of January 2023, Exchange administrators can fill out an online form and, if desired, also provide contact details to discuss possible improvements. Since readers of my blog keep ... Read more

New security updates for Exchange Server (January 2023)

Microsoft has released new security updates for Exchange Server 2013, 2016 and 2019 today. The security updates also include a new security feature, which currently still needs to be activated manually: Click here to download the security updates: The security updates fix the following security vulnerabilities classified as important: New security feature: Certificate Signing of PowerShell Serialization Payload To prevent ... Read more