Can not open 2008 Mac Excel files in 2003 PC Excel

[Turbo36]

Version: 2008 Operating System: Mac OS X 10.6 (Snow Leopard) Processor: Intel I can not open some files I created in Mac 2008 Excel in 2003 Excel PC, I get the "File is not recognized" error. I made sure I saved the files as .XLS (97-2004 format)
The Mac is updated to the latest version and the PC has the latest update (SP3.
I see where other have posted the exact same situation but so far I can't find where someone offered a solution.

 

[Turbo36]

OK, now I really feel foolish. Being new to the mac thing I didn't realize that spotlight writes index files to the USB drive and in my haste to open my file I kept clicking on the index file not the real file. Time to slow down and look closer at what I'm doing.