This most commonly occurs when non-admin users land on an admin-only page in the Management UI (e.g. rabbitmq-server.com:15672/#/users).
This can be resolved by clicking on the RabbitMQ logo in the top-left or by editing the URI in the browser to remove the "/users".
If you believe the user you are using should be an admin you can check their tags by running the following:
rabbitmqctl list_users
This command, by default, will list all users for that given broker along with their specified tags.
If the user should be an admin, but is missing the administrator tag, you can set the user's tag with the following:
rabbitmqctl set_user_tags username administrator
Note: It is possible that changes to user permissions may only take effect when the user reconnects.
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