It looks like you have disabled my plugin so I cannot test it on your site. The error you got was a “No Session” error, which means that your server was not maintaining a persistant session thoughout your login attempts. I can’t tell you why your sessions are not working without access to your site but I can see that you are also using All-in-One WordPress Security maybe there was a conflict with that plugin’s login page additions, I will test that plugin on my site. Which of the two plugins did you install first? and What was the last change you made to you security or serv setting before you started having this problem?
It seems to be working fine now. I can see that both plugins have the protection installed on you login page now and there is no conflict. You server’s sessions are working normally now and you should not get blocked when you try to login. I’m not sure what caused the problem you originally had but looks like it’s working fine now.
Please let me know if you have any more problems with it.