Maybe one more check...

http://support.microsoft.com/?kbid=308360
OFF2000: Error Messages Caused by Nimda Virus When You Open or Save
Files in Office Programs



twm7766 wrote:

I just started having a problem saving a newly created excel file. When I do
a "save as" nothing happens. When I hit esc I can work in the file again.
If I have a previously saved file I can "save" it but I can't "save as".
I've run all the virus checks and ad-ware but nothing seems to help.

--

Dave Peterson