You must be working on a XLS file (in compatibility mode). Either save it as
XLSX format (default format for 2007) or open a new workbook...

You will see columns upto XFD.

"melod" wrote:

For some reason I only have columns to IV in the Excel 2007. This is the
reason I switched to this program since I need more columns. Is there a
setting I need to adjust to get past this?