clear cache

Hi,
1. page1: use huperlink to page2
2. page2 command button process and then redirect to page1
3. now i do not want user to be able to click on browser back button to get back to page2
can anyone please help? I have tried so many different ways of trying to clear cache:
Response.Cache.SetCacheability(HttpCacheability.NoCache)
Response.Cache.SetAllowResponseInBrowserHistory(False)
Response.Expires = 0
Response.Cache.SetNoStore()
Response.AppendHeader("Pragma", "no-cache")
Response.ExpiresAbsolute = DateTime.Now

Nothing seems to work.

Thanks Tim

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