May I know what is the error you receive at the time of activation ? if possible try to attach a screenshot of the same.
Also try the following steps :
1.Delete all temporary files and cookies from IE.
2.Right click on the M icon on the system tray and select product setup.
3. From the options select the option "login" and enter the credentials you used to activate your subscription and continue with the prompts.
Kindly report back if you come across any issues