SMTP: Maximum Number of Recipients Allowed (112761)

SUMMARY

The Microsoft Mail Gateway to SMTP has no maximum number of recipients per mail message. The gateway processes as many recipients as it has available memory. In testing the gateway before release, the mail messages sent to and from 300 recipients, with 420K of RAM available before starting the gateway, was successfully accomplished.

The number of addresses varies depending on:

• amount of free RAM
• size of the addresses, longer addresses take up more memory
• number of users on the gateway postoffice
• number of Microsoft Mail postoffices defined on the gateway postoffice

NOTE: The successful test of 300 recipients is well over the 100 specified by RFC 821. Also note that many mail hosts on the Internet may not support more than 100 recipients.