You have a file named support.dot in a folder where it doesn't belong--or you
have a folder name in an option where it doesn't belong.

I'd open excel
tools|options|general tab
erase any entry you have in the "at startup, open all files in" box
(don't actually remove that folder, just erase that textbox.)

If that doesn't work, maybe your file is in your XLStart folder.

I'd close excel
windows start button|search
for support.dot

and move it out of that folder.

If that doesn't solve the problem...

Chip Pearson has some notes on how to diagnose startup errors at:
http://www.cpearson.com/excel/StartupErrors.htm

And Jan Karel Pieterse has more notes at:
http://www.jkp-ads.com/Articles/StartupProblems.htm

Angel wrote:

...But it opens just fine in Excel 2000
The error: support.dot: file format is not valid

Files coming from one person to two individuals. One of the receiving
persons does not get the error & simply does not open file.

What gives mates?
Thanks,
Angelo

--

Dave Peterson