Hello Craggenmore
Had a similar thing after a disk rebuild and this worked, just substitute excel for whichever of the office suite gives the problem. It will however reset all the excel or whatever settings (ie do you allow macros).
1. Close Microsoft Excel.
2. Click Start, and then click Run.
3. In the Open box, type the following (with the quotation marks):
"C
Program Files\Microsoft Office\Office\Excel.exe" /unregserver
NOTE: If you have installed Microsoft Office 97 to another location, use your correct path for Excel.exe instead.
4. Click Start, and then click Run.
5. In the Open box, type the following (with the quotation marks):
"C
Program Files\Microsoft Office\Office\Excel.exe" /regserver