LoggedIn event not firing

As far as I can see, the following code should work.

<asp:Login ID="Login1" runat="server" OnLoggedIn="Login1_LoggedIn"></asp:Login>
Protected Sub Login1_LoggedIn(ByVal sender As Object, ByVal e As System.EventArgs)
   Response.Redirect("~/test/secure/secure-test.aspx")
End Sub


Unfortunately, the event isn't firing at all.
The login succeeds, but the redirect doesn't occur.
Can anyone see what I've done wrong.
(This is a simplified page I've been using for debugging since the process wasn't working in the real page)
 
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