I have the same problem, but I used my character name for my account, I think. I tried to recover password with the two tips explained in the "I forgot my password" window, but it doesn't work.
For the 2nd solution I've the message "Cannot login to website account. You should start over."
I also removed cookies.
Actually, I think my password just disapeared
or maybe it's the x5 wrong password, as I tried to connect from an other computer without success