XP can’t find files.cab – its on the CD!

I’m having a problem with the latest Outlook patch not taking on my machine. The patch requires the original Office CD, which I have, but the patch fails saying it can’t find files.cab. I look on the CD, and sure enough, it’s right there, but there’s a WinZip icon on it. Apparently WinZip changed the association of the .cab files, resulting in XP not being able to find it.

I’m pretty sure this is a registry issue with the associations, but don’t know where to look to try to fix the issue (and what .cab should be associated with to correct the situation) I did go into properties and change the association to Windows Explorer, but that didn’t clear the problem.

Please help!