In the authentication element, add a forms element to tell the app what form
to use for login, like this...

<authentication mode="Forms">
<forms loginUrl="Registration.aspx" />
</authentication>

Also, make sure you exclude only unauthenticated users from the rest of the
site by adding an authorization element inside your configuration element,
like this...

<configuration>
...
<authorization>
<deny users="?" />
</authorization>
...
</configuration>

The '?' represents all unauthenticated users.

<itinerantCoder />

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