When I try to access this forum from my regular computer, I get the following security rule error:

The page you are trying to access is restricted due to a security rule.

If you believe the security rule is affecting the normal operation of your website, contact your host support team and provide detailed instructions how to recreate this error.
They will be able to assist you with rectifying the problem and adjusting the security configuration if needed.

According to Google, it's a site problem, not a computer problem. I would ask whether anyone else is having the problem, but if they are, they're not here. The error pops after after I enter my user name and password on a Windows 7 computer using Chrome, Firefox, or IE.