Repair/Remove/Install processes for SQL Server 2012 Express get stuck or hung

Question

An instance of SQL Server 2012 Express became corrupted somehow.
I suspect it was related in some way to my use of Entity Framework, but have no proof yet.

When

Answer 1

I had two versions of SQL Server installed. After uninstalling one it froze on SqlEngineConfigAction_remove_validation_Cpu64. The solution that worked for me was just to run uninstall from media. I guess after uninstalling one version it messed up the uninstallation files; so the other uninstallation from control panel add remove froze. so I mounted the SQLServer iso and run from there

setup.exe /Action=Uninstall

Please remember to uninstall all other entries of SQL Server from Add/Remove programs (of course except the entry that is causing problem i.e. Microsoft SQL Server 2008 R2 (64-bit)).

FYI:

1. I had executed the setup.exe /Action=Uninstall from cmd (Run as Administrator) in the mounted iso folder.
2. Also Please restart after the other entries uninstallation. so that all the SQL services are stopped.
3. Make sure all the SQL server services are either stopped or disabled before the restart.

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