Hi Neo,
Hmmm. It's difficult to say if it's an add-in, a corrupted installation or a corrupted profile.
In Excel options, if you set the default save type to XLSX (Excel 2007 worksheet), create a new worksheet and use Office
Button=>Save As can you save that document?
If you Start Word and Excel in Safe mode, hold ctrl key when starting each can you save files without the problems.
If you check
Control Panel=>Advanced=>[Environment Variables]
to see if the temp and tmp varibles are pointing to valid local folders on the hard drive.
Are you able to log in with a different profile and then have the same issues?
==================
Whoa... a few questions there... See responses below...
The password works for xls, but I can't seem to creat an xlsx file. I get
the error message:
Microsoft Office Excel cannot access the file
'C:\Users\Steven\Documents\0995A600'
and the reasons why this might happen. The file being saved has a totally
different name entered of course, and the last part (0995A600) changes with
every attempt.
Are you saving to the My documents folder or to another location?
Both with the same results.
Are all of the files involved on the local hard drive rather than on mapped or network drives?
Both with the same results. >>
--
Bob Buckland ?

MS Office System Products MVP
*Courtesy is not expensive and can pay big dividends*