Furuno Felcom 15 Operator's Manual page 161

8. E-MAIL BY PC
When a file with an attachment is transmitted from land, the LES (e-mail
service provider) separately forwards the file and attachment to the intended
MES. The file name for the attachment as received at the FELCOM 15 is
"ATTACH.DAT." For that reason request that land-based e-mail with
attachment contain the attachment file name in the text of the message.
File and accompanying attachment are sent separately regardless of the
delivery address specified with the auto delivery keyword. The message file
is delivered according to the auto delivery keyword setting and the
attachment goes to the Mail Address set on Mail Gateway.
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