Exchange 2019 CU14 March 2024 Security Update fixed vulnerabilities however it did break a few items which were resolved in this April 2024 Hotfix that they team provided.
Exchange 2019 CU14 Hotfix introduced two new features as well and they are:
- Elliptic Curve Cryptography certificates support in Exchange Server 2016 and 2019
- Hybrid Modern Authentication support for OWA and ECP in Exchange Server 2019 CU14
In this Hotfix, the following items including what broke in the March SU were addressed:
- “We can’t open this document” error in OWA after installing March 2024 SU
- Search error in Outlook cached mode after installing March 2024 SU
- OwaDeepTestProbe and EacBackEndLogonProbe fail after installing March 2024 SU
- Edit permissions option in the ECP can’t be edited
- Outlook doesn’t display unread message icon after installing Exchange Server March 2024 SU
- My Templates add-in doesn’t work after installing Exchange Server March 2024 SU
- Download domains not working after installing the March 2024 SU
The Hotfix is only available for the following versions of Exchange:
- Exchange 2019 CU14
- Exchange 2019 CU13
- Exchange 2016 CU23
You can download the standalone package here:
Below are some screenshots from running the update:
The above error was produced because my lab servers had run out of disk space but a clearing the logs resolved that issue.
The above update does not take long to run, all depends on how powerful the Exchange servers are.
Don’t forget to reboot once you are done and perform your post checks to make sure the services are started, OWA is accessible and your DAG is online along with mail queues.
Hope you find it helpful.