You cannot have an autoresponder with the same
name as an existing POP3 account. The autoresponder must have a unique
name, and it in turn forwards the received mail to another POP3 account.
To resolve any existing problems, either delete your duplicate POP3
account and change the autoresponder to forward to another user, or
delete the autoresponder and create one with a different name and have
it forward to another address other than the one used for POP3.