You can check this by logging into the service. You will be granted full access, to the service, if your Subscription has been activated. See the Subscription information on top-right of the page to confirm.
You will also receive an email indicating that your subscription has been activated. If you have not received this email, see the answer to Question 1 under the section titled "Mail Related".
Normally, it takes less than 30 minutes for the subscription to get activated (after making a Credit Card payment). If the subscription is not activated after a reasonable amount of time (1 hour) contact your nearest CMIE branch.