>>>>>Hi everybody,
>>>>>
>>>>>I added NODEFAULT and return in Checkbox Click event, but it still changes the value.
>>>>>
>>>>>How can I prevent it?
>>>>>
>>>>>Thanks in advance.
>>>>
>>>>Set it to ReadOnly or Enabled = false
>>>
>>>No one with good suggestions of resolving the problem? It's probably a bug - but I'm not sure what workaround options are?
>>
>>How about

IF (ChangeNotAllowed)
>>  this.Value = IIF(this.Value=0,1,0)
>>ENDIF

in the Click event (g)
>
>Right, but it doesn't sound like a very good interface as it will switch and then switch back.

It doesn't just not sound good - it sounds horrible (g) OTOH I've no idea whether flipping it in the Click() will happen before any ControlSource gets changed.....