Every PC gateway channel consists of two autonomous systems. One system is running PMDF. The other system is the PC Local Area Network (LAN). In this context, the PC LAN consists of at least one file server and one or more PCs which are file service clients. The PC LAN hosts some e-mail system, such as cc:Mail or Da Vinci eMAIL.

The two systems must cooperate for the gateway to work, so their configurations must be kept synchronized. Yet frequently these two systems are controlled by two different administrative entities. If, for example, the PC LAN administrator changes their router setup, PMDF can no longer be able to deliver mail to certain PC post offices. Yet correcting this problem can not be within the jurisdiction of the PMDF administrator who can not even have access to the impacted post offices. Configuration synchronization often implies a high degree of administrative coordination because of issues like this.

Each PC mail system gateway (other than the Lotus Notes channel) has three major components:

1. PMDF's PC channel programs converting messages between MIME and the PC import/export file format specific for that PC mail system.
2. The "support PC" moving messages between the proprietary mail format in the post office to the documented external format in import/export files.
3. The "transfer PC" optionally moves the import/export files between the PC and PMDF system.