Looking into it further I found that the problem only shows when logging into a different user account than the MSI was installed in. The user account that the release is installed into directly doesn't have that problem. As in when joining the system to a domain and logging into the system as a domain user, double clicking a mp3 file won't open winamp. The problem isn't clear to me, I may have been wrong about the double \\, as that doesn't seem to be directly the issue. In any case removing the double \ does seem to fix it. I tried the new release on a clean system, didn't fix it. It's a small issue though, I may just try to get it to work w reg fixes like OrcoXP suggests. Any ideas?