Please help me for EnableWindow of main dialog.

[C++ Programming]

Hi all,

i working on dialog box application ,here the main dialog box have some buttons and some other controls,
on clicking on on buttong any other child dilaog box is open ,when any child dialog box is open main dialog box is not accessible,

but in my case at certain point on dialog is open by running thread over the main dialog box,and when this is open he main dialog is accessible when one child dialog box is open over it, and oter buttond and dialog box also working on this condition,

i m using EnableWindow(0) for main dialog when open the child dialog box from thread but its not working.

please help me how can i solve this.

i want when any child dialog is open over the main dialog box the main dialog sholud not be accessible.

thanks in advance.