Issues installing SQL 2008 R2 SP update

We recently had issues installing an SP update on an SQL server. Someone along the way had configured a registry key that was blocking the upgrade.

I could fix it myself, under HKLM\Software\Microsoft\Update Services\Server\Setup I changed the value for the "wYukonInstalled" key from 1 to 0 and the updater didn't look for the Windows Internal Database anymore.

Upgrade SCE to SP1 fails:

'via Blog this'

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