Tag Archives: BuildToBuildUpgrade

Exchange uninstall fails with BuildToBuildUpgrade error

Uninstalling is typically not an issue. One of my Exchange 2019 servers (running on Windows 2022 Server Core) have been running for quite some time, but I had to uninstall it.

Running the setup application failed with a BuildToBuildUpgrade error, almost immediately after starting the setup:

PS C:\> setup.exe /mode:uninstall /IAcceptExchangeServerLIcenseTerms_DiagnosticDataOn

Microsoft Exchange Server 2019 Cumulative Update 12 Unattended Setup

Mailbox role: Mailbox service
Mailbox role: Client Access service
Mailbox role: Transport service
Mailbox role: Front End Transport service
Mailbox role: Client Access Front End service
Management tools
Setup previously failed while performing the action "BuildToBuildUpgrade". You can't resume setup by performing the action "Uninstall".

The Exchange Server setup operation didn't complete. More details can be found in ExchangeSetup.log located in the <SystemDrive>:\ExchangeSetupLogs folder.

If have seen setups failing before, but normally during an upgrade to a newer setup, but never during an uninstall.
Just like other setup failures, check the registry for Action and Watermark entries in the HKLM\SOFTWARE\Microsoft\ExchangeServer\v15. Only the MailboxRole had these entries, the ClientAccess and HubTransport did not have these entries.

Delete the Action and Watermark keys and resume setup.
Unfortunately, I don’t know why this happened in the first place since my Exchange server has been running without issues for a longer time.