Unable to make fields required on Inventory Utility Remove Bins

Hi

Users keep accidentally running the Inventory Utility Remove Bins with no criteria.

I have tried modifying the form to make all of the from and to fields required. They are now highlighted as bold, but the process event ignores this.

I have tried VBA for window before close

Private Sub Window_BeforeClose(AbortClose As Boolean)

If Me.FromBin = "" Then AbortClose = True
End If

End Sub

Again, this seems to only work on Save and OK, it ignores the logic for a process event.

Private Sub FromBin_BeforeLostFocus(KeepFocus As Boolean, CancelLogic As Boolean)

If Me.FromBin = "" Then KeepFocus = True
MsgBox "Required"
End

End Sub

I have also tried to keep focus on the field if they try to move off the field without a value. The MsgBox appears but it loses focus.

Bit stumped on this one.

Thanks

Tania