When I start Excel I get the error message "Subscript out of range". This happens only when Excel starts. It happens whether you open an existing workbook or new blank one. There is NO error number.

Sounds like a script is running when you start excel, try holding down shift whilst you start excel and see if it goes away. If it does you DO have a script and will need to loacte it to either correct it or remove it. It could be in your excel start-up area or in you personal workbook.