When attempting to install a Microsoft Exchange Cumulative Update, the readiness checker may fail and stop you from proceeding with the upgrade and installation.
You will be presented with the following error, or one similar:
There is a pending reboot from a previous installation of a Windows Server role or feature. Please restart the computer and then run Setup again.
After restarting the server, and re-attempting to install the Exchange CU, it will continue to present this and stop you from proceeding with the installation.
There’s a few different things that can cause this. I experienced this issue when trying to upgrade Exchange 2016 CU18 to Exchange 2016 CU20. This issue can also happen when upgrading from Microsoft Exchange 2019 CU versions, as well as earlier versions of Exchange 2013.
I found a few posts online referencing to delete two registry keys, “UpdateExeVolatile” and “PendingFileRenameOperations”, however these didn’t exist for me.
I figured I’d try to install a feature, specifically something small that I may or may not ever use, to see if it would work and to see if it would clear whatever flag had been set for the pending restart.
First, I left the Exchange CU installer window open on the prerequisite check, opened the Server Manager and installed the TFTP Client. After finishing, I hit retry and it continued to fail.
I restarted the server, ran the CU installer again which got stuck on the pending restart. This time I closed the Exchange CU upgrade, installed the “Telnet Client” feature, opened the CU upgrade again, and it finally worked and proceeded!
So with the above in mind, to bypass this issue you must:
- Restart Server
- Launch Exchange CU Installer
- Wait for readiness check to fail (warning of a pending reboot), close installer
- Install a feature with the Server Manager, such as “TFTP Client” or “Telnet Client”
- Open Exchange CU Installer
- Install Microsoft Exchange Cumulative Update successfully!
Hope this helps! Leave a comment and let me know if it worked for you!