You will have a received your license keys via email and in order to activate DC Media using one of these keys, you must have Internet access from the computer that you have installed DC Media on.
Run the DC Media application that you have installed. A software activation window will be displayed:
Locate the license key matching the application name displayed in the window. Click Next
Enter your license key and click Next to activate the software. If successful, a message will be displayed indicating the the software has no been activated. In the event of unsuccessful activation, double check the license key that you have entered by running the software again, and double check that your Internet access is indeed working on the PC.