Troubleshooting and codes

Microsoft is still in the process of rolling out new mail servers. One thing that is new about these is some new codes on their error messages. This has led to questions and speculations as to what is going on.

host outlook-com.olc.protection.outlook.com [104.47.9.33] said: 550 5.7.1 Unfortunately, messages from [10.10.01.01] weren’t sent. Please contact your Internet service provider since part of their network is on our block list (AS3150). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors.

This particular error code caused all sorts of confusion because AS#### is a way of identifying networks (autonomous system number). AS3150 identifies network space owned by NTT America and reading the error message seems to indicate that Microsoft is blocking all of NTT. They’re not.
AS means “Anti-Spam” and the numeric code is for Microsoft to troubleshoot things on their end.
Another example of one of the new error messages is:

451 4.7.500 Server busy. Please try again later from [<ip-address>]. (AS843) [<someserver>.prod.protection.outlook.com]

There appear to be a number of these codes. I’ve seen specific mention of codes like  AS3140, AS3160 and AS844.  All of these are intended for internal use at Microsoft. If you’re filling out the sender support form, absolutely include that number. I don’t know for sure that it will help speed things up, but it cannot hurt. Plus, you’ll look like you know what you’re talking about if/when you need to escalate things.
A number of senders have asked if MS will be sharing what the different codes are. I haven’t seen any answer other than “they’re for internal troubleshooting.” That doesn’t mean they won’t be listed specifically, but I expect updating the postmaster website documentation is low down the list of things to do during the transition.
In any case, I wouldn’t focus on the specific AS codes for delivery troubleshooting until and unless MS releases them to the public. Focus on the codes that are public on the Postmaster website.
In summary:

  • Hotmail / Outlook / Microsoft isn’t blocking NTT America / AS3150.
  • The new AS codes stand for AntiSpam
  • The numbers are intended for internal, not external, troubleshooting
  • Check the postmaster site for the codes intended for external troubleshooting.

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Microsoft deprecating SmartScreen filters

At the beginning of the month Microsoft announced that they were deprecating the SmartScreen filters used by the desktop Microsoft mail clients. These are the filters used in Exchange and various version of Outlook mail. This is yet further consolidation of spam filtering between the Microsoft free webmail domains, Office365 hosted domains and self hosted Exchange servers.  The online services (hotmail.com, outlook.com, Office365, live.com, etc) have been  using these filters for a while. The big change now is that they’re being pushed down to Exchange and Outlook users not hosted on the Microsoft site.
EOP was developed for Outlook.com (and friends) as well as Office365 users. From Microsoft’s description, it sounds like the type of machine learning engine that many providers are moving to.
Microsoft has published quite a bit of information about these filters and how they work on their website. One of the best places to start is the Anti-spam Protection FAQ. Something senders should pay attention to is the final question on that page: “What are a set of best outbound mailing practices that will ensure that my mail is delivered?” Those are all things  deliverability folks recommend for good inbox delivery.
Poking around looking at the links and descriptions, there is a host of great information about spam filtering at Microsoft and how it works.
A page of note is their Exchange Online Protection Overview. This describes the EOP process and how the filters work.
MS_filterProcess

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Email predictions for 2015

Welcome to a whole new year. It seems the changing of the year brings out people predicting what they think will happen in the coming year. It’s something I’ve indulged in a couple times over my years of blogging, but email is a generally stable technology and it’s kind of boring to predict a new interface or a minor tweak to filters. Of course, many bloggers will go way out on a limb and predict the death of email, but I think that’s been way over done.
ChangeConstant
Even major technical advancements, like authentication protocols and the rise of IPv6, are not usually sudden. They’re discussed and refined through the IETF process. While some of these changes may seem “all of a sudden” to some end users, they’re usually the result of years of work from dedicated volunteers. The internet really doesn’t do flag days.
One major change in 2014, that had significant implications for email as a whole, was a free mail provider abruptly publishing a DMARC p=reject policy. This caused a lot of issues for some small business senders and for many individual users. Mailing list maintainers are still dealing with some of the fallout, and there are ongoing discussions about how best to mitigate the problems DMARC causes non-commercial email.
Still, DMARC as a protocol has been in development for a few years. A number of large brands and commercial organizations were publishing p=reject policies. The big mail providers were implementing DMARC checking, and rejection, on their inbound mail. In fact, this rollout is one of the reasons that the publishing of p=reject was a problem. With the flip of a switch, mail that was once deliverable became undeliverable.
Looking back through any of the 2014 predictions, I don’t think anyone predicted that two major mailbox providers would implement p=reject policies, causing widespread delivery failures across the Internet. I certainly wouldn’t have predicted it, all of my discussions with people about DMARC centered around business using DMARC to protect their brand. No one mentioned ISPs using it to force their customers away from 3rd party services and discussion lists.
I think the only constant in the world of email is change, and most of the time that change isn’t that massive or sudden, 2014 and the DMARC upheaval notwithstanding.
But, still, I have some thoughts on what might happen in the coming year. Mostly more of the same as we’ve seen over the last few years. But there are a couple areas I think we’ll see some progress made.

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Thoughts on Hotmail filtering

One of the new bits of information to come out of the EEC15 deliverability discussions is how Hotmail is looking at engagement differently than other webmail providers.
Many webmail providers really do look at overall engagement with a mail when making delivery decisions. And this really impacts new subscribers the most. If there is a mailing where a lot of subscribers are engaged, then new subscribers will see the mail in their inbox. Based on what was said at the webinar earlier this week engagement has no effect at Hotmail outside of the individual user’s box.
I’ve certainly seen this with clients who’ve tried trimming subscriber lists but that doesn’t really help get mail moved from the Hotmail bulk folder to the inbox.
 
Instead of subscriber lists, Hotmail is really looking at bounces. They’re watching the number of nonexistent accounts senders are mailing to and they’re counting and a sender hits too many bad addresses and that is a major hit to their reputation.
All of this makes remediation at Hotmail challenging. Right now, we can remediate a bad reputation at a lot of ISPs and the filters catch up and mail starts flowing back to the inbox. Hotmail has set up a system that they say is “hard for spammers to game.” This seems to translate into hard for legitimate senders to fix their reputation.
Hotmail is, IMO, the current tough nut in terms of deliverability. Develop a bad reputation there and it’s difficult to fix it. I’m sure it’s possible, though.

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