IMAP Connection Limits

Allow __ connections per user on a single IP address:
Many IMAP clients use a new connection for each folder that a user accesses. You can specify the maximum number (default 15).

Terminate idle connections after __ minutes:
This option shuts down unused IMAP connections after a time limit (default 30 minutes).

Automatically delete

When this option is selected, read and unread messages are deleted after a time limit you specify (default is 120 days for unread, 90 days for read starting when the message is first read).

Delete unchanged mail hosts after 1 day of inactivity

Selecting this option helps minimize the size of the host list. It erases from the host list domains that did not receive or send mail or were unchanged by the administrator for one day.

Allow SMTP relay when host is a backup for destination

This option allows messages to be forwarded to a backup server, overriding local anti-spam settings.

Send undeliverable Non-Delivery Reports to Postmaster

When this option is selected, the Postmaster is informed if a non-delivery notification is returned (which often indicates a spam account).

Allow Non-Delivery Reports for bulk mail

This option sends non-delivery notifications for mail sent using a bulk mail setting (typically from mailing lists). Use this option with care because non-delivery reports to a mailing list might cause mail loops.

Use case-sensitive IMAP Folder Names

When this option is selected, the server distinguishes between upper- and lowercase names for IMAP folders (for example, "Apple" and "apple" would be different folders).

Related topic

Advanced mail server settings