>>I would like to know how to prevent my user from closing the project using the "Close (X)" at the top rightmost side of VFP screen. I am wondering if this can be disabled.
>>
>>Thanks a lot,
>>
>>Nerissa
>
>Intercept the QueryUnload() Event. NODEFAULT will avoid the default behaviour, in this case, closing the form.

Not if it's the main VFP window. That only works for user defined forms.