Sys.WebForms.PageRequestManagerParserErrorException behaves diffrent on production

I have a generic Exception Handler class and iam using a AJAX error Control.

When i get the exception i pass it to a Error page using Server.Transfer(url) but started getting "Sys.WebForms.PageRequestManagerParserErrorException"

Then i replaced Server.Transfer by Response.redirect(url,false)

Which worked on my local machine but when i deploy it on production it opens in a new window.

To solve this problem i tried using

                Dim strbuilder As New StringBuilder()
                Dim currentpage As New Page
                strbuilder.Append("<script type = 'text/javascript'>")
                strbuilder.Append("window.open('")
                strbuilder.Append(url)
                strbuilder.Append("');")
                strbuilder.Append("</script>")
                currentpage.ClientScript.RegisterStartupScript(Me.GetType(), "script", strbuilder.ToString())

Which doesnt hel and get a blank message ??

is there any other alternative to avoid Sys.WebForms.PageRequestManagerParserErrorException