Logins erratic or not working

New site on 7.0.4 and the logins stopped working altogether.  I (as admin) can go to the administration panel and log in, but if I try and login from the front page, it says that my username or password is incorrect.

I have taken a user profile, went into the admin settings, changed the password, and then tried to login with that, and having no success.

I am desperate! Can anybody help?  I have had people in the website testing all day yesterday, and no issues whatsoever, now...... no one can login.

The only difference was that I installed the Facebook Connect module. I will uninstall, but do not think that is the issue.

Any ideas?  Why is it that the login will work for the BACKEND admin section, but not a single login on the entire site will work through any other interface on index.php, join.php, or otherwise?

I would like to know what files directly process the logins from the public side. MY login works on the admin side, but will not work on join.php, or the ajax login popup.

I would love to see someone help me with the critical system error.

This might be related to the anti-spam filters new to dolphin 7.0.4.

One of the filters blocks all IP addresses. If you have enabled the filters, then you must make sure zomgbl.spameatingmonkey.net. is deactivated. That one is for testing and blocks everything.

I have checked the antispam filters, and all are deactivated at present.  I am perplexed and do not wish to start re-copying files again, but I guess I will have to figure this one out.