Can't opening RabbitMQ web supervision interface after uninformed install

I've hallowed a latest RabbitMQ server
(rabbitmq-server-3.3.0-1.noarch.rpm) on a uninformed Centos 5.10 VM
according to a instructions on a executive site.I've finished this many
times before during growth and never had any issues. However, this time we
can't record into a supervision web interface controlling a default
guest/guest user.In a logs, we see a following:=ERROR REPORT====
4-Apr-2014::00:55:15 ===webmachine error:
path="api/whoami""Unauthorized"What could be causing this?