We don't know. It is reported far too often to be just an incident. Most
people don't even know there is a choice!
But it's easy to correct:

ToolsOptionsGeneral, Uncheck "R1C1 reference style"

--
Kind regards,

Niek Otten

Microsoft MVP - Excel

"Bob in Buffalo" <Bob in wrote in message
...
What will cause column headings to change from letters to numbers in excel
2000?