you have to use in web.config in in your aspx file
the maintainScrollPositionOnPostBack=true
<system.web>
<pages maintainScrollPositionOnPostBack="true" validateRequest="false /">
usually with that attribute the page mantain the scoll position during postbacks.
if you have problems in that you can look that reference :
Maintain Scroll Position in Panel, Div[
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OR
(a bit tricky) you can save the scroll position on click into a cookie
and at page load (postback) you read the position from the cookie
in my application i have rad ajax manager and
i use that code to save and retrieve scroll position from cookies
the cookies fuction are available
here [
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but my needs are quite differents than your try the solutions above before