The Session &1 has no roles assigned.
&1 - The Session ID
The folder list for a session could not be determined as the session has no roles assigned.
Check whether a user is logged into the session (Use the administration menu item Utilities→Surrogate).
If a user is logged in, check whether the user belongs to any roles. If not - assign the roles necessary for the user to access the site.
If the user has only belongs to roles specified as being IntranetOnly, check whether the IP-address specified for the session corresponds with the IP-Mask specified on the Site Settings. If the user should be able to access the application from outside the intranet, he must belong to at least one role that is not specified as being for intranet use only.
If the user has roles assigned that should have been assigned to the session, check whether the Session.RemoveRole/Session.RemoveAllRoles APIs has been called.
If no user is logged in, check the above for the user specified as the anonymous user on the site settings.