[unisog] Hotmail delivery issues

Alan Amesbury amesbury at oitsec.umn.edu
Thu Jun 22 16:45:18 GMT 2006

Beers, James W. wrote:

> It was recently brought to my attention that our users are experiencing
> 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 experienced
> 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 was
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 that
the real-world counterpart to e-mail is USPS certified mail, not Fedex
same-day delivery.

Alan Amesbury
University of Minnesota

More information about the unisog mailing list