Hi Vincent,
Use of the fill handle
http://www.mvps.org/dmcritchie/excel/fillhand.htm

I think you will also have to make up a custom list also
described on the page.
A, B, C, ...., X, Y, Z, a, b, c, d, ... , x, y, z .

try filling down if it doesn't work you will need th custom list.
---
HTH,
David McRitchie, Microsoft MVP - Excel [site changed Nov. 2001]
My Excel Pages: http://www.mvps.org/dmcritchie/excel/excel.htm
Search Page: http://www.mvps.org/dmcritchie/excel/search.htm

"Vincent" wrote in message ...
I know there is a way that I can type in a in cell a1,b cell a2, b , cell a3,
c and then drag to the bottom of the column and it will continue with d,
e,f, etc but have forgotten.Can somebody please remind me again.
Thanks