A user would have successfully logged on but their mailbox was busy so the POP3 server could not gain access to it. The mailbox may be busy for several reasons:
- An IMAP4 client is currently logged on to this account;
- A POP3 client is already logged on to this account;
- A new message may be delivered at exactly the same instant
In this case, session Undefined was processing a logon from a POP3 client at Undefined. The user affected by the mailbox being busy was Undefined@Undefined.
To resolve this problem you will need to ensure that the user is not using multiple protocols to access email at the same instant or simply ask them to try again. Note: GMS does not have any issues with multiple access to the same email box, the issue only occurs when two protocols require simultaneous checks for an instant.
Keywords:failed logon POP3 mailbox busy 8139