Uninstall woes

Having bowed to pressure from the family and installed Microsoft Office 2007 on one of the family PCs, I figured that there is no further need for the copy of Microsoft Works that came pre-installed on the machine. But when I tried to remove Works, I was prompted to insert the installation CD!

WTF? Why on earth should this be required? Most malware is easier to get off your system than this piece of crap.

Anyway, I can't comply with the request because the CD was not supplied with the system when we bought it. Grrr...