One problem with this is that it will give the message even when A2 has something in it.
How about:

=IF(AND(A1<"",A2=""),"<< Complete A2 !!","")
--
Earl Kiosterud
www.smokeylake.com
-----------------------------------------------------------------------
"Max" wrote in message
...
One way ..
In B2: =IF(LEN(A1)<0,"<< Complete A2 !!","")
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
---
"Jeff" wrote:
Hi,

I like to know how do I set up in excel to setup a field to be a mandatory
field if the field beside it has data ?

For example: If A1 has data, A2 can not be a blank field and prompt error
message.

Depends on the interp, and the alert phrase <g

Perhaps: "<< Complete A2 !!" in the earlier alerts better as:
"<< Enter / Re-enter A2 !!"
which then caters for giving a message to re-enter A2
even when A2 has something in it (prior to entry in A1).
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
---
"Earl Kiosterud" wrote in message
...
One problem with this is that it will give the message even when A2 has
something in it. How about:

=IF(AND(A1<"",A2=""),"<< Complete A2 !!","")
--
Earl Kiosterud
www.smokeylake.com