To find the installed .NET Framework versions manually (versions 4.5 and later)

 

Open regedit.exe

Open the following key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full

Check for Release. Just having the Release key shows that the .NET Framework 4.5 or newer has been installed

The value of Release shows which version of the .NET Framework is installed

Value of the Release DWORD	Version
378389	.NET Framework 4.5
378675	.NET Framework 4.5.1 installed with Windows 8.1
378758	.NET Framework 4.5.1 installed on Windows 8, Windows 7 SP1, or Windows Vista SP2
379893	.NET Framework 4.5.2

Note: You need to reboot before the correct release is shown.