repair your software. If you go into the Add/remove programmes in Control Panel go to the item in the list. you should see 2 options on the right ?/remove carn't remember what this says.
Or put your disk in CD and see if it will give you an option to Repair.
CAB File is compressed programme for a software components eg windows items are installed in CAB Files. Its not the CAB file you need to worry about but the repair of Front Page.