What is alert 8153?
GMS has reported an error because the remote POP3 client has issued an APOP command with a syntax error. The APOP command requires a user name and password digest in order to log on the user.
In this case, session Undefined was processing a command from Undefined. The command
was rejected with
-ERR Illegal command
To resolve this problem you will need to tell your user to upgrade to the latest version of their mail client or ask them to use GMS Webmail to get access to their email.
Keywords:syntax space APOP POP3 8153