Search notes:

Registry: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\VisualStudio\SxS\VS7

This key lists all Visual Studio installations ( The %VSINSTALLDIR% directory) with their respective versions, for example

C:\> reg query  HKLM\SOFTWARE\Wow6432Node\Microsoft\VisualStudio\SxS\VS7
15.0    REG_SZ    C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\

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