Treeview and Modal Popup Extender

Hi all,

I have a image button which opens a modal Pop up in master page, and I have a tree view in another ASP.net Page(say Parent)( build from previously mentioned Master Page). when i click on image button in Parent Page.. POP up is opening and I have a button inside that popup. when i click on that button the popup is getting closed and parent page is getting refreshed. I don't want the parent page to get refreshed.

can any one please help me ??

Thanks in advance.

Lokesh