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A Solution Twenty Years in the Making (Microsoft Finally Killed Reply-All Storms)

May 13, 2020

Email is considered an old technology. I guess that’s true. I mean anything invented before you were born is old. Email as we know it has a start date. August 1982 is when modern email was born. That was the date that RFC 821 was approved. RFC 821 defines how an email is created on a computer network. At least it defines how SMTP email is created. There used to be lots of different email types, X.400, MHS, Easylink, CompuServe, MCI. Each had their own protocol. If you want to read the birth of a technology, you can read RFC 821’s full text here.

SMTP won the email war. That’s why your email address is [email protected].

But, originally email was pretty simple. You could send to one person. Oh, and you kind of had to send it directly to their computer. People wanted to be able to send to multiple recipients. Fortunately RFC 822 added additional features including sending to multiple recipients. And email became something you could send in the middle of night and the system would deliver whenever it could.

This was the beginning of the dreaded Reply-All storm. You know, when you send that cookie recipe to the cute guy in accounting, but you accidentally include the entire company on the CC: line. And then everyone, including your boss, replies “Don’t send to everyone.” And of course, to make sure everyone else knows, they Reply-All. That’s the wrong thing to do, and people reply back to not use Reply-All. And that makes it worse. And you have a storm.

The best defense to a Reply-All storm was education. It only took one “cookie disaster” to learn your lesson. But, education didn’t always work. Several years ago I wrote a blog post about the 1997 Reply-All storm that was so bad, it forced Microsoft to fix the problem. The entire story is here.

Someone found they were part of a distribution list that they didn’t recognize. They ended up sending an email to the distribution list asking to be removed. Everyone on the list got a copy of the email. They also didn’t know they were on the this list. (Called Bedlam DL3) Others responded and asked to also be removed. And they used Reply-All. And then, the net nannies jumped in to say, “Don’t Reply-All. You make it worse.” And, of course they sent it to Reply-All. Forty-five minutes and fifteen million emails later the resulting storm crashed the email system of the world’s largest software company, Microsoft. (Remember this was 1997. Before the rise of Google.)

Microsoft made some immediate changes, including restricting distribution lists, limiting the maximum number of recipients on an email. Ten years later in 2008, they added the ability for administrations to kill Reply-All storms.

This week, again, about ten years later, Microsoft finally put the final nail in the coffin of Reply-All storms. The new version of Exchange is now smart enough to identify a Reply-All storm on its own and kill it.

It’s been over twenty years since that Bedlam3 meltdown at Microsoft. And almost forty years since email was first visualized in RFC 821. Typically in the tech industry, you have to race to keep up with the latest new thing. But, sometimes, the newest thing is actually an old thing. Like, invented before you were born, old thing.

By the way, I’m older than email and lived through my share of email storms.

Stay Safe

Rodney M Bliss is an author, columnist and IT Consultant. His blog updates every weekday. He lives in Pleasant Grove, UT with his lovely wife, thirteen children and grandchildren.

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