opening an excel 2003 spreadsheet in excel 2007

[bobby02169]

hello all, I am not that experienced in excel soplease bear with me if i am
asking a simple question.
When I try to open an excel 2003 .xls spreadsheet in excel 2007 I get the
following message.
"The file you are trying to open, 'Blank INVOICE.xls', is in a different
format than specified by the file extension. Verify that the file is not
corrupted and is from a trusted source before opening the file. Do you want
to open the file now?"
A little info. I just upgrade my microsoft office from 2003 to enterprise
2007.
i am using windows XP Pro
I having never had this problem before and my thinking is somehow my excel
spreadsheets got corupt during the transfer. Is there a solution or software
etc. to try and fix this problem?
Thank you in advance for any help
Bobby

[trip_to_tokyo]

Bobby, I think it is unlikely that the file got corrupted during transfer.

If you are happy that the file is from a trusted source then just answer yes
to the question that the software asks.

You could, as a precuation, virus check the file before doing the above.

If my comments have helped please hit Yes.

Thanks.