Microsoft Word/Excel files have weird icons/generic icons

Not quite sure when it started, but a friend's computer has some strange icons on the desktop. Basically, the icons are the generic icons Windows uses to display the file type it doesn't know how to open. However, when you click on it, they can be opened by Word or Excel.

Upon on further checking, the files with wired/generic icons are actually Word or Excel files. Other Microsoft Office applications don't seem to be affected.

Followed the methods at https://superuser.com/questions/505859/microsoft-word-files-have-weird-icons-suddenly, but nothing helped.

One possible cause of this issue is that the files in the C:\Windows\Installer\{91140000-0011-0000-0000-0000000FF1CE} corrupted. Note that 91140000-0011-0000-0000-0000000FF1CE may change based on your version of Office. You can go to C:\Windows\Installer and search 'wordicon.exe' to locate the exact folder. This folder also can be found in Registry at \HKEY_CLASSES_ROOT\Excel.AddInMacroEnabled\DefaultIcon.

Once you open the folder, find out the *icon.exe files with generic icons, copy the good ones from C:\Program Files (x86)\Microsoft Office\Office14 (again, this may change based on your version of Microsoft Office) and overwrite the ones in C:\Windows\Installer\{91140000-0011-0000-0000-0000000FF1CE}. Restart the computer and the problem should be solved.