Windows Server update (KB5020873) causes Veeam B&R failure

[Maplestar1969]

All our backup jobs failed in past few days. Error logs show below messages
-- 1/19/2023 12:01:48 PM :: Error: The RPC server is unavailable. RPC function call failed. Function name: [GetSvcVersion]. Target machine: [Veeam.mac.local:6160].
-- 1/19/2023 12:23:31 PM :: Processing HRServer Error: The RPC server is unavailable. RPC function call failed. Function name: [InvokerTestConnection]. Target machine: [Veeam.mac.local:6162].

I checked 1st error and GetSvcVersion points to Installer Service (VeeamDeploySvc) stopped. Started the service manually and 2nd error pops up. The possible reason points to Microsoft updates.
Uninstall recent Microsoft server updates from Veeam B&R server and re-run backup jobs, it back to normal.

[HannesK]

Hello,
and welcome to the forums.

While uninstalling the update might have solved your problem, I doubt that it is a source of the problem in general. Otherwise we would have tons of cases and forum posts around that topic recently. I recommend checking with Veeam support (please post the case number for reference)

Best regards,
Hannes

[Maplestar1969]

Thank you. Actually, I went through similar posts in forums first and found below. Because backup jobs failure happened in past 2-3 days, so I checked Windows update history and tried to uninstall latest updates and re-run backup manually.
I am not sure if KB5020873 is the root reason of this issue. But I will keep eyes on it and see if it happens again.

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