FindControl() ?????

Hi,
   I have master page and two aspx page. Both page have master page connected to them...
Now i have one image button in page1 which is inside update panel and update panel is inside the content place holder.
Now when i click on image button then through postbackURL i redirect to page2.
There in page_Load() i need to find which imge button was clicked.

But FindControl() returns null...
How to Handle this????


Thanks.

 

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