The basic requirement for a validation rule is that the expression used for
the rule evaluate to True if the data is valid and False if the data is
invalid. In your case, you have two scenarios. Each scenario must be
represented by an expression.
Scenario 1: If Field 1 is blank, Field 2 must be blank.
An expression that evaluates to True only if both these conditions are met
is:
([Field1] = "") AND ([Field2] = "")
Scenario 2: If Field 1 is non-blank, Field 2 must be non-blank.
An expression that evaluates to True only if both these conditions are met
is:
([Field1] <> "") AND ([Field2] <> "")
Put them together with OR (because either one or the other scenario is
possible):
(([Field1] = "") AND ([Field2] = "")) OR (([Field1] <> "") AND ([Field2]
<> ""))
Make sense?
--
Sue Mosher, Outlook MVP
Author of
Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
LEM said:
I am in the process of designing an Outlook Form. Field 1 & Field 2 are
both text fields. If Field 1 is blank, Field 2 must be blank. If Field 1
is non-blank, Field 2 must be non-blank. How can I apply both of these
rules to Field 2?