There was an issue on one of the security items that has now been relaxed. This should take care of the issue with people not being able to log in once getting to the site.
If you are still having issues, be sure to check the listed items. If everything is set up correctly, and you use parental control software, please check to see if it works if you turn off the parental control software. If it does, then you may need to check your settings for our site. Some parental control software scans the site. This will block you as you appear to be a bot.