How do I change my column headers?

[mrockwood]

My Column headers are numbers (1,2,3) instead of letters (A,B,C). How do I
fix this?

 

[Dave Peterson]

in xl2003 menus:
Tools|Options|General tab
uncheck R1C1 Reference style

In xl2007:
Office button|Excel Options|Formulas|Working with formulas
uncheck R1C1 Reference style


Excel picks up this setting from the first workbook you open in that session.

If you have a co-worker who likes R1C1 Reference Style and you're unlucky enough
to open a workbook that he saved as the first workbook in that session, you'll
be making the same change again.