POPcon Advanced Configuration Options

Eventlog Entries

POPcon can write status and error information to the Windows eventlog. Use this option to enable or disable eventlog entries as needed. When enabled, POPcon logs each mail retrieval cycle, errors, and key processing events to the Application log.

Recipient Address Manipulation

POPcon allows you to remove a configurable string from the start or end of recipient mail addresses before delivery. This is useful when your external mail provider adds prefixes or suffixes to addresses that do not match your internal Exchange or SMTP server addresses.

• Remove string from start of recipient address — strips a fixed prefix from each recipient address.
• Remove string from end of recipient address — strips a fixed suffix from each recipient address.
• Regular expression support — both fields accept PERL-type regular expressions for complex pattern matching. This enables flexible transformations such as stripping variable-length substrings or rewriting address patterns.

Remove Read Receipt Requests

When enabled, POPcon strips read receipt request headers (Disposition-Notification-To) from incoming messages before delivery. This prevents internal users from inadvertently sending read confirmations to external senders.

Processed Mail Header Fields

POPcon examines specific mail header fields to determine the intended recipient of each message. The following header fields can be individually enabled or disabled:

• Received…for — parses the Received header’s “for” clause to extract the envelope recipient address.
• Delivered-To — uses the Delivered-To header field, commonly set by providers such as Gmail and other large mail hosts.

Enable or disable each option via its corresponding checkbox. In most configurations, both options should remain enabled to ensure accurate recipient detection.

Replacement of Domain Names

The domain replacement feature maps external domain names to internal domain names. This is required when your external-facing mail domain differs from the domain used on your internal Exchange or SMTP server.

For example, if your provider delivers mail addressed to user@example.com but your internal server expects user@internal.local, you can add a mapping from example.com to internal.local. POPcon rewrites the recipient domain before forwarding the message via SMTP.

• Multiple domain mappings can be configured simultaneously.
• Mappings apply to all recipient addresses extracted from mail headers.