If you accidentally chose a wrong program to open a file, it seems to stick as the recommended program forever. It’s very annoying and loses your time on opening files.
To remove a program from the Open with list, rung Registry Editor (regedit.exe), browse to
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\ . Here you must find the extension of the file in question. For example, if the extension is .ac3, open HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.ac3 . Now, click OpenWithList . Here you see a list of programs to open the file extension, listed with latin letters. Delete any lines corresponding to programs you don’t want to be recommended for opening this extension. Reboot, and the Open with is now trimmed to your likes.