Question : Change Required Error Message - Access 2007

I have certain fields in a form set to required value, if you don't enter a value it pops up a message box saying 'You must enter a value....'

My question is, how do I change the message that the box prompts you with?

Answer : Change Required Error Message - Access 2007

open the table HealthCheck in design view
select the field Hea_ClientID field

set the following property

Required  NO
Validation rule   Is not Null
Validation Text  "< Place your own message here >"