Nested User Controls - Button onclick event will not fire

Hi Guys,

I have a usercontrol which is loaded into an aspx page.  Within the usercontrol it also loads up other usercontrols directly into a placeholder depending on which list item is being clicked.  When I click the button the onclick event in the code behind isn't being triggered - is there something I have to do in order for nested usercontrols to be dealt with appropriately?  

ASPX

------ usercontrol (Main user control)

-------------user control loaded into the above user control

--------------------button clicked - but doesn't fire event.

Thanks,

 

Mark
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