It allowed me on, to change my password, but when I log out and log back in, it complains that it can't display the webpage. This happens in both Firefox and IE. I am puzzled.
I don't understand. How could you post this if you can't see the web page?
But anyway... try removing all cookies for the site. That is a trick that sometimes works with mysterious problems at any site.
Yow! I see the same symptom! 
We are working on it.
Should be better now. Post again if you still have problems.
The problem is in the plugin system.
When I globally disable we can login.
If I enable it, the problem returns.
OK, I think I fixed it and isolated the plugin problem. (Hopefully!)
Please post if this problem returns. Thanks.