Re: Intermittently Unable To Send Email

"Malcolm" <nospam@xxxxxxxxxx> wrote in message
news:h8mdncbxS5x8LE_fRVnygQ@xxxxxxxxxxxx
> Hello 'N.Millner', you are right.
>
> The last entry into the SMTP Log is 354 go ahead. From what I understand,
> this means that the server is ready to accept the actual message.
> So, my email client should then be sending the actual message,
> but for some strange reason it isn't.


Unfortunately that log entry may also mean that it has already sent
some of it and it is waiting for an acknowledgment for that piece
before continuing. The only way to know for sure is to take a packet
trace.


>
> I removed the AV software, but I am wondering if it was not a clean install
> and something was still there. Stranger than that, I don't know why the
> problem is intermittent.


Would "intermittent" correlate with the size of the message?
In that case perhaps you have an MTU size issue to deal with.
I don't really understand how message size is supposed to be
affected by the MTU size because the MTU is so relatively small
that multiples of them must be used to send even small messages.
Perhaps it is just a case that the probability of connection failure
increases due to the extra problems there would be recovering
on each oversize packet from that problem? Are your sends
sometimes slow too?

<title>KB314825 - How to Troubleshoot Black Hole Router Issues</title>

Again, a packet trace would probably expose problems such as this.


HTH

Robert Aldwinckle
---


.

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