Error 401

Reader not authorized to read this file:

What does this mean?

1. Please make sure that the link you are trying to access is preceded by www. That is, it starts with www.hdcn.com or https://www.hdcn.com and not with hdcn.com or http://hdcn.com.

2. If you got a password box that requested a username and password this means that the file you are trying to access is in a password-protected subdirectory of HDCN, and which requires a username and password. If you then press ENTER again you get this 401page.

If the file you requested is in the FREE ZONE of HDCN, then you tried to access it without first registering with HDCN. To register, go to the the registration link on the home page of HDCN and register, and get a free zone loginID and password.

If you already are registered and your FREE ZONE login and password is not working, then chances are that the file you want is in the KEY ZONE of HDCN. You can't access it until you get a paid subscription, at which time your loginID and password are upgraded to access material in KEY ZONE subdirectories. To subscribe, follow the links on the home page of HDCN (upper left).

FREE vs. KEY zone files:
Look at the message on the password box. If it says "Please enter your username and loginID for the KEY ZONE of HDCN", and your FREE ZONE password is not working, then the problem is the requirement for a paid subscription.

Forgot your password?
If you're sure that you registered in the past, then you can find your password at at this password link.

If you forgot your password, Please send an email to with password in the subject line. Your password and loginID will be mailed back to you automatically.

Duplicate logins
HDCN periodically removes duplicate logins. When we do, we send an email to the most recent login/password combination to inform the user that they should use the most current username. All CME/CEU certificates from duplicate logins are transferred over to the most recent login. If your username/pw dose not work, you may be using an older, duplicate login that had been deleted in the process of maintaining a clean user database.