3. ASoft .NET Version Detector. This program is a small and lightweight portable tool that gives information on all the different versions of .NET Framework that are installed on a machine.
Old Version of Microsoft .NET Framework 3.5 Download Nov 19, 2007 How to Install .NET Framework 2.0 3.0 and 3.5 in Windows Oct 09, 2017 List of .NET framework versions – Jonathan Parker's Blog Dec 05, 2014 Microsoft .net Framework version 3.5 : Security
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP. See how to go to a Registry key with one click. The installed versions are listed under the NDP subkey. The version number is stored in the Version entry. For the .NET Framework 4 the Version entry is under the Client or Full subkey (under NDP), or under both subkeys.
How to Install .NET Framework 2.0 3.0 and 3.5 in Windows Oct 09, 2017
Microsoft .net Framework version 3.5 : Security
How to Check .NET Framework Version in Windows 10 Computer