POPcon SMTP/Exchange Server Settings

Exchange Server Name

Enter the hostname or IP address of the internal Exchange or SMTP server that POPcon delivers retrieved mail to. This is the server that accepts incoming messages via SMTP and routes them to individual user mailboxes.

SMTP Port

Specify the TCP port on which the target SMTP server listens for incoming connections. The default value is 25, which is the standard SMTP port. Change this only if your server uses a non-standard port configuration.

SMTP Timeout

Configure the number of seconds POPcon waits for a response from the SMTP server before treating the connection as failed. Increase this value if your server is slow to respond under heavy load; decrease it to detect unresponsive servers more quickly.

Advanced Error Handling

POPcon provides configurable responses to specific SMTP error conditions encountered during message delivery. The following error types can be individually configured:

• User unknown — the SMTP server rejected the recipient address because no matching mailbox exists. Configure whether POPcon should re-route the message to the postmaster, discard it, or leave it on the remote server for retry.
• IP blocked — the SMTP server refused the connection because the sending IP address is blocked or not authorized. This typically indicates a relay restriction or firewall rule. Configure the action POPcon should take when this error occurs.
• Action not taken — a general SMTP failure indicating the server could not complete the requested action (e.g., mailbox full, temporary server error). Configure whether POPcon should retry delivery, skip the message, or escalate to the postmaster.