Please explain the logic when using DataErr from start to finish. Do you try to inclue all errors in the Form_Error section that might be encountered somewhere in the application or in a form? Where does the code reference or activate a specific DataErr such as the one listed below?
Private Sub Form_Error(DataErr As Integer, response As Integer)
response = acDataErrContinue
Select Case DataErr
MsgBox "Account Number already exist for this REGU."