[unisog] Hotmail delivery issues

Bill Martin BMARTIN at luc.edu
Thu Jun 29 18:47:22 GMT 2006

We to experience this, quite often as a matter of fact.  Going back
through the SMTP logs, there are thousands of time-outs, disconnects
before the transactions initiate/complete.

When I first saw this, I thought it was a temporary issue, but it
happens way to often to be temporary.

-bill martin-
Information Technology Service
Loyola University Chicago

>>> Alan Amesbury <amesbury at oitsec.umn.edu> 6/22/2006 11:45 am >>>
Beers, James W. wrote:

> It was recently brought to my attention that our users are
> issues when sending e-mail to Hotmail.  I did some testing from our
> domain and messages to Hotmail are being queued, but not from other
> domains.  I also sent e-mail from Yahoo to Hotmail and also
> a significant delay in delivery.
> Is this 'normal' for Hotmail?

I see this sort of thing frequently for Hotmail, and occasionally for
other large e-mail providers (Yahoo comes to mind).  The most recent
in the past day or two, when Hotmail's MX hosts were returning "Out of
memory" errors to mail delivery attempts.  SMTP was designed to handle
trivial problems like this gracefully, which it does by requeueing the
message and trying later.  Again, this is normal.

SMTP is designed to be a store-and-forward, delivery-with-receipt
protocol, and I've never heard it described as a reliable,
instantaneous-delivery mechanism (at least not by anyone with a strong
knowledge of how it works).  It might be worth reminding your users
the real-world counterpart to e-mail is USPS certified mail, not Fedex
same-day delivery.

Alan Amesbury
University of Minnesota
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