Try this:

DataValidationSettingsAllow:Custom, Formula: =A2<"yes"
Input message: Uncheck "Show input message when
cell is selected
Error alert: Check "Show error alert after invalid
data is entered, Style: Information, Fill "Title" and "Error message" as you
like (e.g. Fill next cell!)
OK

--
Regards!
Stefi



€žAndrew Mogg€� ezt Ã*rta:

Is there any way to have a pop up occur to inform user that to continue a
value must be entered into a certain cell. eg if user selects 'yes' the a pop
up flags them to enter a value in adjacent cell