How to fix Header Manipulation of below code

Question

Dim footer_strQSPersonalize As String = Request.QueryString("SitePersonalize")

Dim footer_strCookiePersonalize As String

'East Scan Fix Header manipulation LPYT 10/8/2015

If (Server.HtmlEncode(Request.Cookies("SitePersonalize") Is Nothing)) Then

footer_strCookiePersonalize = ""

Else

footer_strCookiePersonalize = Server.HtmlEncode(Request.Cookies("SitePersonalize").Value)

End If

'

_Personalize = _Util.GetPersonalization(Request.ServerVariables("server_name"), footer_strQSPersonalize, footer_strCookiePersonalize)

Server.HtmlEncode(Response.Cookies("SitePersonalize").Value = _Personalize)

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