Forum Discussion
Annoying message when launching Excel...
Every time I launch Excel in Microsoft 365 I get the annoying message "Excel cannot open the file Book 9.xlxs because the file format or file format is not valid. Verify that the file extension matc...
Thank you, Sir. That folder is empty.
Let's see if anyone else has an idea...
Indeed, let us hope so. This matter is shredding what little sanity I have left.
Thank you again for your original reply.