There was a security error when trying to login

I installed the Zen Cart 1.3.9 on a Win2008 Server/IIS7, http://112.120.68.55/store
the installation was fine and I could start the Shopping page.
However, I could not go into the Admin area, it reported
"There was a security error when trying to login"

Please any one help?

First do you have a SSL Certificate?
Has it been installed?

If you do - I will bet that it is not issued to 112.120.68.55
Bit to your domain name

If the loaded url does not match the domain name the certificate is issued to it will error

I found the problem was caused by the browser

I can successfully login with I/E and FireFox but failed with Opera.

I donot know whether this is Opera problem or ZenCart problem!?

I donot know whether this is Opera problem or ZenCart problem!?
It is exactly the problem as I described - the cert is not issued to an IP number