jjknuutt - 2022-09-15

When I needed two different versions of Codesys to be installed because of different hardware units requiring them, I ran into the problem of opening the project files neatly with the appropriate version. Windows did not show the Codesys version in the "open with" menu. It turns out that that can be easily edited with regedit at
Computer\HKEY_CLASSES_ROOT\Local Settings\Software\Microsoft\Windows\Shell\MuiCache
key(s)
C:\Program Files (x86)\3S CODESYS IFM\CODESYS\Common\CODESYS.exe.FriendlyAppName
C:\Program Files\CODESYS 3.5.16.50\CODESYS\Common\CODESYS.exe.FriendlyAppName
(in my case, your installation folder path might differ)

So renaming the values of those will show up in the "open with" menu like in the attachment.