This solution covers troubleshooting steps to resolve an issue where a Guest Admin is immediately logged out upon logging into the SonicWall.
User is a member of the SonicWall default Group Guest Administrator
The Guest Services are enabled on the Zone configuration
HTTPS Management is enabled on the interface
After logging in as a Guest Administrator user, you are redirected to https://IPadddress/dynLoggedOut.html
When the feature Use System Dashboard View as starting page is enabled, it requests access to the Dashboard page to any administrator logging in to the SonicWall whereas Guest Administrators do not have permission to access it.
Navigate to System | Administration | Uncheck the box Use System Dashboard View as starting page | Accept the changes.