Synchronet v3.19b-Win32 (install) has been released (Jan-2022).

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Table of Contents

Synchronet Message Base

The SMB format and library specification v1.21, circa 1993:

Header Fields


  • The RECIPIENT header field contains a single name or full-address of the message recipient, in US-ASCII or UTF-8 characters
  • The RECIPIENTLIST header fields contains the original comma-separated list of all message recipients (excluding CC's), in US-ASCII or UTF-8 characters
  • The RFC822TO header field contains the MIME-encoded version of the RECIPIENTLIST header field, if applicable

Every message must have a (single) RECIPIENT header field. The RECIPIENTLIST header field is optional and an RFC822TO header field should not exist if a RECIPIENTLIST header field is not also present.

See Also