>Does anyone know how to programatically read the "Hide File Extension" option of Windows Explorer using a Windows API? I've been searching with no luck so far.
>
>I handle tech support calls fairly often that deal with a bug in Word 97 automation having to do with this setting, and I would like to programmatically check for this setting on app startup.

Sergey has pointed you to the right key. If the value is zero, it means that file extensions aren't hidden. Any other value indicates that they are. Usually, the value in this case is 1.