How to do - B2 is only valid if B1 is zero
 

Microsoft office 2007 XL. How do I perform a validation where cell B2 is only
valid if cell B1 is blank or zero. Have read the help text on this including
the section on "what is allowed on the context of another cell". As a result
I tried many different things but cannot get it right (if it can be done).
The data validation only appears to have equal to, greater than, less than
etc., for a field compared to the field being validated. It does not seem to
have the scenario where a field is valid solely on the value of another field
(i.e. if(And(B1<0,B2<0),error) ) . Can anybody help me?

How to do - B2 is only valid if B1 is zero
 

Hi,
go to data validation,custom, enter

=OR(B1="",B1=0)

enter an error alert message

"declaire9" wrote:

Microsoft office 2007 XL. How do I perform a validation where cell B2 is only
valid if cell B1 is blank or zero. Have read the help text on this including
the section on "what is allowed on the context of another cell". As a result
I tried many different things but cannot get it right (if it can be done).
The data validation only appears to have equal to, greater than, less than
etc., for a field compared to the field being validated. It does not seem to
have the scenario where a field is valid solely on the value of another field
(i.e. if(And(B1<0,B2<0),error) ) . Can anybody help me?