I found out today that I was locked out of my own blog! Sounds like it was the WordPress Login Lockdown plugin. I got the following error message:
ERROR: We’re sorry, but this IP range has been blocked due to too many recent failed login attempts.
To unlock myself, I went into the MySQL database for my WordPress installation, and ran the following SQL code. This code sets the release_date to a date in the past so that I can login again. Thanks to Nick for the SQL code.
update wp_lockdowns set release_date=”2017-01-01 00:00:00″ where lockdown_IP=”<IP address>”;
If the above does not work, run the following SQL command. Note that this will reset the “release_date” for all IP addresses, not just yours.
update wp_lockdowns set release_date=”2017-01-01 00:00:00″ where lockdown_ID > 0