Very strange behavior with SMTP and attachments. I can always get an email to send (and receive) with just an attachment or just a message, both from my laptop and using a server script. But with both a message and an attachment, I am no longer guaranteed that the email will send. No errors reported by FMS or capturing with a script function. This can be quoted text and/or inserted fields.
It appears, although not consistently, that if I add a lot of text with many return characters, then it helps. I had success for a few runs with one line of text followed by 6 returns, but then that started to fail. I removed the text entirely and the emails with attachments worked again.
Is it possible that the email gets confused with both, thinking that they are one block of text in some cases? I've tried adding bullets and special characters, and nothing seems to resolve consistently. In my case, I'm attaching a FMPSL file, so there is the possibility that the attachement (UNIX LF, UTF-8) has something to do with it.