Hi Karuna,
When you refresh the page the script is most likely not executed because it requires a user action to trigger it.
If you want to have a RadWindow shown on the initial load of the page you can show it in the Sys.Application.Load event: http://msdn.microsoft.com/en-us/library/bb383829.aspx.
An alternative is setting its VisibleOnPageLoad property to true, but this will have it show up after each page load (postback).
Regards,
Marin Bratanov
Telerik
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