ASP.NET Webpage expired Cache issue
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I appear to have a problem and I cant find a solution....I have an ASP.NET search form and when user clicks on a result and then clicks the back button the browser, the user is then directed to a page that says 'Webpage has expired'

I know it s cache issue and this is what I have tried...

    protected void Page_Init(object sender, EventArgs e)
    {
        Response.AppendHeader("Cache-Control", "no-cache"); 
    }

and

    protected void Page_Init(object sender, EventArgs e)
    {
        Response.AppendHeader("Cache-Control", "no-cache, no-store, must-revalidate");
        Response.AppendHeader("Pragma", "no-cache");
        Response.AppendHeader("Expires", "0");
    }

and none of these solution seem to work, any one have any idea why?