SMTP Protocol Returned a Permanent Error.

HCL Notes/Domino 8.5 Forum (includes Notes Traveler)

Subject: SMTP Protocol Returned a Permanent Error.

Feedback Type: Problem

Product Area: Domino Server

Technical Area: Functionality

Platform: Windows

Release: 8.5.1

Reproducible: Intermittent

We have a intermittent problem with our mailserver.
Sometimes a couple of mails are non deliverable and come back with a message saying : "SMTP Protocol Returned a Permanent Error." And thats all. A resend of the same mail after receiving the error goes as it should.

It happens a few times a day, but i cant predict when. At 99% of the cases when that error occurs, there is a mail that comes back with a defined error like exceeding size or domain not found and then followed by some mails with the "SMTP Protocol Returned a Permanent Error."
But when i check the logs i found 2 mails with that error without any other problems at that time.
Sending an Email with the same (wrong) address doesnt trigger the problem.

When i send the email with the wrong address i almost instantly get an errormail returned. But when i check an email with the same wrong domainname which is followed by a couple of "SMTP Protocol Returned a Permanent Error." emails, i can see that they were send way earlier then the error occurred.

In the notes log i can see the errors, but the smtp server i am sending to, only sees an error for the unknown domainname and thats all, the other errors are not in their logs.

We reduced the number of transferthreads as we thought it was maybe a speed problem, but it looks like it made it only worse. When it occurred it resulted in more then 40 emails with the "SMTP Protocol Returned a Permanent Error." message.
After increasing the number of threads to 8 it only affects 2 or 3 mails when it occurres.

Anyone some suggestions what i could try?

Btw : Lotus Domino 8.5.1 , Clients 7.04 and 8.5
No Antivirus on the mailserver. No firewall on the outgoing mail.

Feedback number WEBB8E7C7Q created by ~Kim Elfoozenetsi on 02/18/2011

Status: Open
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