This error message relates to the following errors: ERR12 and ERR1800.
The BLERK! ERROR 5 message happens when there's a problem loading AOL mail. Though this is often a temporary issue, there are a few steps you can take to get your back in to your mail quicker.
Restart your browser:
Sometimes the old "turn it off and on again" solution actually works! Just close out whatever browser you use, then start it back up again. Once the browser has been restarted, go to to mail.aol.com and enter your username and password.
Clear your cache, cookies, and history:
Another option to fix the error messages would be to clear your browser's cache, cookies, and history. Doing this will wipe out all the little unwanted bits of info that have been stored in your browser, resetting it and making it overall run better.