Whenever an unhandled exception occurs on our site, I want to:

• Send a notification email
• Clear the user's session
• Send the user to a error page ("Sorry, a problem occurred...")

The first and last I've had working for a long time but the second is causing me some issues. My Global.asax.vb includes:

Sub Application_Error(ByVal sender As Object, ByVal e As EventArgs)
    ' Send exception report
    Dim ex As System.Exception = Nothing
    If HttpContext.Current IsNot Nothing AndAlso HttpContext.Current.Server IsNot Nothing Then
        ex = HttpContext.Current.Server.GetLastError
    End If
    Dim eh As New ErrorHandling(ex)
    eh.SendError()

    ' Clear session
    If HttpContext.Current IsNot Nothing AndAlso HttpContext.Current.Session IsNot Nothing Then
        HttpContext.Current.Session.Clear()
    End If

    ' User will now be sent to the 500 error page (by the CustomError setting in web.config)
End Sub

When I run a debug, I can see the session being cleared, but then on the next page the session is back again!

I eventually found a reference that suggests that changes to session will not be saved unless Server.ClearError is called. Unfortunately, if I add this (just below the line that sets "ex") then the CustomErrors redirect doesn't seem to kick in and I'm left with a blank page?

Is there a way around this?