If IsNull(Me.SomeField) Then
Msgbox "SomeField is null. Please enter a value", vbOKOnly
Me.SomeField.SetFocus
Cancel = True
End If
If Me.SomeField > 55 And Me.SomeOtherField > 22 Then
Else
Msgbox "SomeField and/or SomeOtherField are out of range. Please fix.",vbOKONLY
Cancel = True
Me.SomeField.SetFocus
End If