Here's what I'm trying to do: I want the program I'm developing to be the default program for WMV files, whether launched from the hard drive or streamed from a site.

When activated, my program takes the command line arguments

Dim param As String = Command()

And uses that parameter to activate its video player.

I changed the default action for the WMV file type, for both Open and Play, to: "C:\myprogram.exe" "%L"

This works fine whenever I double click a WMV on the hard drive. The trouble comes when I click on a link to a WMV file, for example www.mypage.com/video.wmv

Instead of opening the file with my program, Windows opens a save file dialog, with an error message at the bottom saying "The file you are opening cannot be opened by the default program. It is either corrupted, or has an incorrect file type." My program is never even activated (I put in extra error catching and message boxes to be certain of this.)

Does a link to a WMV send different parameters than one on the hard drive? Or is there a compatibility issue with the code line I used?