Not able to subscribe any subscription

Hi Team
I have installed RHEL Server V6.3 successfully and also register on REDHAT network "A Red Hat subscription supports you from concept to deployment" but not able to subscribe any subscription. It throws me : NO Subscription available.
Anybody faced this issue ? Please help me
due to this, I am not able to update anything on server.

Thanks

Where is it showing that message? What are you running?

Did you run rhn_register ?