Email issue on customer box

We have a very strange situation with email on a customer box. It seems that if we send a message through the QtmmSendMail API (therefore going through MSF and the built-in SMTP), it's anybody's guess whether it goes through at all, and if it does, it could take minutes or hours to go through.

They have UZAEMON's SNDM installed. The first few times I tried it, I got an immediate error message, telling me that the message had been rejected because of an authentication issue. This in spite of the fact that they have a number of applications that actually use SNDM to send email.

I eventually got them to drop the proverbial other shoe: when they use SNDM, they use the SMTPHOST parameter, passing a value of "EXCHCAS.FOO.BAR" (not the real value, for privacy reasons).

When I tried sending test messages through SNDM, with the SMTPHOST parameter set as specified, they went through consistently and reliably, in a matter of seconds. And this "EXCHCAS.FOO.BAR" appends a "confidentiality notice" to the message. And so I spent a good chunk of yesterday modifying an automatic notation program to go through SNDM.

But that raises the question, is there something that can be done with the system's MSF and SMTP configuration, so that QTmmSendMail also goes through this "EXCHCAS.FOO.BAR" server as well?

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JHHL