First he said:
This time, when I tried to log in, I received the message "Cookies are required to log in to this site. You will not be able to login until they are accepted."
As I allow cookies, I really have no clue what the problem is, but I'm close to giving up.
Then he said:
I played around with my anti-spam software and browser cookie settings, so it should really work now, but still...when I try to log in, I get the message "This action is available via POST only. Please press the back button and try again."
Any ideas? Thanks.