[Plugin: Lockdown WP Admin] not working

Can you give me the exact error message that it gives you?

For some reason I cannot get this to work. I installed the latest version, chose the http auth option and I am locked out with no way to start my administration without deleting the plugin folder. I even deleted everything off my server and started from an old backup, reinstalled a fresh plugin and still get the same issue. Please help me. Thank you!