HKLM\Software\Microsoft\.NetFramework\
InstallRoot [REG_SZ]

Installtion: c:\WINDOWS\Microsoft.NET\Framework\

HKLM\Software\Microsoft\.NetFramework\policy\v2.0
50727 [REG_SZ] : 50727-50727

Version: 2.0.50727

HKLM\Software\Microsoft\.NetFramework\policy\v4.0
30319 [REG_SZ] : 30319-30319

Version: 4.0.30319

Available Runtime Versions The runtime determines the available runtime versions by enumerating the keys and values in the registry under HKLM\SOFTWARE\Microsoft\.NETFramework\policy. Each key identifies the major and minor version of the runtime. The values under each major and minor key identify the build number. For example, the key HKLM\SOFTWARE\Microsoft\.NETFramework\policy\v1.0 with a value of 3705 indicates that version 1.0.3705 of the .NET Framework is installed.

A directory with the same version number as specified in the registry must also exist under the .NET Framework installation root. The directory names are preceded with the letter v. For example, version 1.0.3705 of the .NET Framework would be installed in <InstallRoot>\v1.0.3705.

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