>>>>>>I ran your program and it returns the correct association. Computer magic ?
>>>>>>But I still get a "No association." error.
>>>>>
>>>>>When you right click on the .PPT file, what action verb is on the top of the shortcut menu? Try to run with default action
>>>>>

>>>>>*lnResult=ShellExecute(FindWindow( 0, _SCREEN.caption), "Open", tcDocument, "", "c:\temp\", 1)
>>>>>lnResult=ShellExecute(0, "", tcDocument, "", "", 1)
>>>>>

>>>>
>>>>"Show" I changed the "Open" to "Show" and BINGO!
>>>
>>>Did you test it with PowerPoint installed?
>>
>> Yes. And guess what - I get a "No association." error when PowerPoint is installed.
>>If I change the "Show" back to "Open" on the PowerPoint machine the program runs again.
>
>So, does the syntax with "" instead of action work all the time?

The "" default works with PowerPoint and with just the Powerpoint Viewer.