'enable cookies to login', even when they are
Whenever I try to log in, I get "You have to enable cookies to be able to login to this site," even though they are. I know it's not a problem with my computer, because I've tried logging in with three different users on two different computers, with Firefox and IE on one and just IE on the other.
This started happening when I was changing some administration options, and I needed to test something with a user with standard permissions, so I opened another window (same browser) to log in with the standard permissions user. The first window was still at the administration menu. After I tried logging in as the standard user, this message appears whenever anybody tries to log in from anywhere.