Admin Role - protected admin folder

I'm trying to create a login system with roles.
In the admin folder the web.config has


<configuration>
    <system.web>
        <authorization>
            <allow roles="Admin" />
          <deny users="*" />
        </authorization>
    </system.web>
</configuration>


Problem is if a logged in member accesses or tries to access the admin folder the member is sent/redirected back to the ~/login.aspx page even when he is logged in.
Is there a way to send to another page possibly with a message that he doesn't have access to admin folder. Or even another suggestion.


thanks.





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