Notary, refusenotary, nonotary Channel Options

SMTP DSN extension support (, ,
The  and (the RESTRICTED)   channel options control whether client TCP/IP channels  attempt to use the SMTP DSN extension (defined in RFC 3461). The  channel option is the default on SMTP over TCP/IP channels.

The  channel option, if set, disables the use of the SMTP NOTARY extension. Its use on SMTP client channels is RESTRICTED, and it is normally used only on LMTP client channels. Note that setting   or an   channel option on a channel implicitly sets.

New in 8.0.1 is the  channel option. This RESTRICTED option disables the DSN extension in the SMTP/LMTP client and additionally, the SMTP server. (The DSN extension is never offered by the LMTP server.)

See also:
 * lmtp Option
 * TCPIP channels
 * Notification messages
 * Notification message MTA options
 * Notification messages and postmaster messages channel options
 * SMTP and LMTP protocol channel options
 * Channel options