> If i used 1000 columns in excel 2007, then safe the file to be use in excel
> 2003, it will be possible to see all the columns when opening the file in
> 2003?or information will be lost?
Note that you've posted to a Mac XL newsgroup, which is not necessarily
the best source for WinXL info.
However, in this case, it's pretty clear cut: as the dialog will tell
you when you try to save the 1000 column workbook as an .xls file,
anything outside 256 columns will NOT be saved, and any formulae with
references to columns > 256 will return the #REF! error.