Q: About a week ago, I had an email to an Outlook contacts group fail to transmit. The following message was returned:

Your message did not reach some or all of the intended recipients.

Subject: Test

Sent: 2/2/2018 2:09 PM

The following recipient(s) cannot be reached:

This was followed by a list of all the intended recipients. Cox blames Microsoft and Microsoft says it is Cox. I can send from the Cox mail website. I don't know if it is a filter that Cox implemented or what. I cannot send to any contacts group since this started happening. I have friends who have similar problem and none have the same Outlook version but all use Cox as ISP. The problem started at the same time for all of us. I also have friends with Outlook who use Cox and do not have the problem.

I found one possibility that there was a bad address in the contacts group but we are using different groups that are failing.

– Bob D., Shalimar

A: Sounds like this is not necessarily a “Thanks, Bill!” moment, but rather a “Thanks, Pat!” moment (the latter being Patrick J. Esser, president of Cox Communications, for those of you Geeks who keep track of this sort of thing). All things being equal, assuming you didn’t change any settings on your system to cause the problem, the more likely target for blame is Cox, for the simple matter that installed software does not suddenly change the way it operates. Servers, however, are constantly being tweaked and subtly changed as they are maintained. When something that has been working suddenly stops working, if nothing locally has changed, the cause must lie elsewhere. So, Bill is probably off the hook for this week, and you may direct your ire toward Patrick, until you get satisfaction.

I would refer you to my column from a couple weeks ago (I.G.T.M No. 556, March 2018) in which I gave a high-level explanation of how email works by drawing an analogy between email and physical mail. Reader Kimber J. was having an issue that’s not too fundamentally different than yours – specifically, she was having problems sending email. It just so happens she is also a Cox user, and I threw Cox under the bus in that column also. Nothing against Cox, mind you, but if they are the source of the problem, I have no hang-ups about calling them out for not providing proper assistance to customers who seek it.

You didn’t mention how many recipients were in the Contacts Group to which you are trying to send. If the number is reasonably small, the first thing I would try would be to send a separate email to each of the group members, and see if you get different results. An email sent to a group should not fail in its entirety because a single address in the group failed. However, heaven only knows how the mail server is configured. If one of the addresses in the Group is blacklisted, perhaps Cox is inferring a blacklist of the entire group. There may also be a practical limit on the number of recipients to which Cox allows you to send an individual email. This would probably be strictly an anti-spam measure, since spammers tend to send the same email to dozens, hundreds, or even thousands of recipients. If your email exceeded Cox’s maximum recipient threshold, it would naturally have been blocked. If that was the case, you can rest assured it had nothing to do with the contents, or even the recipients, but rather a simple count of intended recipients.

Under the part of the error where it says “The following recipient(s) cannot be reached” and enumerates the failed email addresses, does it not provide the reason for the failure? If so, you might as well forget everything I said above, and concentrate on those individual errors as the source of the problem.

Beyond that, my advice to you is the same as that which I gave to Kimber: call Cox Customer Service. If they’re “blaming” Microsoft it’s because you’re leaving them with the impression that Outlook is erroring. It appears to me that it’s working perfectly fine. It seems like the Cox email service is returning unexpected errors, and Outlook is simply correctly reporting the error messages that are being returned. It should be obvious to anyone that takes the time to examine the problem (especially a customer service agent at an ISP as big as Cox) that this is the email provider’s problem, and not Microsoft’s.

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