SMTP: Attachments Named ATT1, ATT2, ATT# (99716)

SUMMARY

Microsoft Mail users opening messages originating from a SMTP mail environment may show attachment names as "ATT1," "ATT2," and so on.

The Microsoft Mail Gateway to SMTP generates these attachment names if the message is coming from a foreign SMTP mail system (meaning not another Microsoft SMTP Gateway) which adheres to the RFC 1154 standard of handling attachments.

NOTE: If the message is sent from another Microsoft Mail SMTP gateway, a Microsoft-proprietary header field called "X-MS-Attachment:" exists, which holds the filename of the attachment. The creation of this header is compliant with the RFC 1154 standard.

Because the header is proprietary, other SMTP vendors will not have it as part of the message. In this case, the SMTP Gateway creates its own attachment names as "ATT1," " ATT2," and so on.