21 Dec 2006 at 01:49 - 2
Taken from the PlayNC website, this is exactly what I did. Does it take time for it to take effect maybe?
Adding Keys to Existing Game Accounts
Question
How do I add additional access keys to my existing Guild Wars game account?
Answer
If you would like to add additional access keys to your account, please follow the instructions provided below:
Launch the Guild Wars game client.
Click the Create Account or Add Access Key option on the login screen.
Click the Add the Access Key to an existing Guild Wars account checkbox.
Enter your account e-mail address and password, and click the Next> button.
Enter your new access key, and click the Next> button.
Click the Next> button to accept the addition of your access key.