Msexchange, nomsexchange Channel Options

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Microsoft Exchange gateway channels (msexchange, nomsexchange)

The msexchange channel option may be used on TCP/IP channels to tell the MTA that this is a channel that communicates with Microsoft® Exchange gateways and clients. Use of the option tells the MTA to try and accomodate nonstandard behavior on the part of Microsoft Exchange. Exactly what nonstandard behaviors are dealt with is subject to change.

Currently the msexchange channel option on a channel configured to allow TLS use (see the *tls* channel options) causes advertisement (by the MTA's SMTP server) and recognition (by the MTA's SMTP client) of the non-standard TLS capability string, in addition to the standard STARTTLS capability string, to indicate that TLS is supported.

New in 7.0.5, setting msexchange on a destination channel will cause the MTA, if performing any sort of MIME processing operation, to remove any Content-disposition: header line from any text/calendar message parts, as despite Content-disposition:'s long-standing existence as a standardized header line, not to mention the basic MIME rule that unrecognized Content-* header lines should be ignored, Microsoft® Outlook's handling of text/calendar parts is disturbed when such parts have a Content-disposition: specified. So specifying msexchange on a channel sending to Microsoft Exchange, if text/calendar parts will flow through that channel, should allow Microsoft Outlook to process calendar parts more successfully.

nomsexchangeis the default.


See also: