Re: how to trace outgoing SMTP connections failures ?

They contain neither frames nor packets - it captures traffic at the application layer. You'll find out about application-layer interaction between SMTP hosts - SMTP commands/verbs like HELO/EHLO, and responses to those (including error codes).

Logging SMTP protocol activity

If you want to dig deeper to the network layer and peek into the packets (for example, to figure out why a network connection or SMTP session isn't established.... ), you'll need to fire up a network capture tool like NetMon or Ethereal and capture packets from/to that host.
Bharat Suneja
MVP - Exchange
NEW blog location:

"Pierre" <pierre.bru@xxxxxxxxx> wrote in message news:6b0d5509-dd43-4dfc-bea4-1a7b89c044ed@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
I thought SMTP logs only contained successful frames...


On Nov 26, 10:06 pm, "Susan" <scon...@xxxxxxxxxxxxxxxxxxxx> wrote:
you can crank up smtp protocol logging, but it won't be much fun trying to
trace something like that...

Susan Conkey [MVP]

"Pierre" <pierre....@xxxxxxxxx> wrote in message


> hi,

> our exchange server use an outgoing SMTP relay which is not very
> responsive :/
> the admin of the relay says it's not true (of course...)

> is the a way to trace the outgoing SMTP connection which do not
> succeed (mainly for timeout reason), forcing the mail to be re-queued
> for another attempt ?

> TIA,
> Pierre.


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