"Rob Bovey" wrote in message
...

Choose Data/Validation and select the Custom option from the Allow
dropdown. Then enter the following formula:

=OR(MOD(A1,10)=0,MOD(A1,15)=0)

Cool. Thanks Rob. You live and you learn. (You in this case is me :-)
Now why is this suddenly "custom" and not "formula is" like in conditional formatting ?
Strange.

Best wishes Harald
Excel MVP

Followup to newsgroup only please.