What percentage of emails are undelivered or duplicates?

I’m changing my email address and that means I need to contact all organisations who send me emails, and change the address details. What I have found is that the only companies that support changing email addresses are those that need to send info that is unique to the subscriber - things like bank statements. Companies sending out impersonal information, such as the weekly Straight Dope digest, don’t let you change your email address. You simply subscribe again with your new address.

I don’t know what percentage of email service providers send back AccountDoesNotExist errors, and what percentage of mailers actually do anything about such messages. If I die next year there will be two copies of the Straight Dope winging their way to my unattended addresses, potentially for ever !

So, does Cecil (or any of the teeming millions) have any idea what (vague) proportion of email traffic comprises these duplicates? I won’t dare ask how much impact they have on network performance and wastage of capacity

check out the mailchimp deliverability benchmarks

Both of these should be near 100%. Bouncing of undeliverable mail is a requirement of the mail transfer protocol, so all mail providers should be doing this.
Culling undeliverable addresses is not required, but failing to do so will increase the likelihood of being blacklisted by anti-spam services, so any bulk mail service worth its salt should be doing this. Certainly there are some home-grown systems out there not doing so, but the majority of legitimate mass mailings are doing this.

The impact of these undeliverable messages is utterly inconsequential compared to the amount of untargeted spam that clogs up the networks. I’ve heard estimates of the amount of spam at 70% and up of all internet traffic.

IF you’d like a solution to keep getting these mass mailings: keep track of all the ones you receive in a week or month and resubscribe for the ones you want to keep.

This sort of thing is why I have my own email domain and have it set to forward everything to my own email provider. I can change the email provider at will with no impact on my email.

What about abandoned e-mail accounts? Someone signs up for a free e-mail address, uses it for a while, and then stops. Maybe they’ve switched to another provider, maybe they’ve died, maybe they only signed up for one purpose and then forgot about it. But the provider doesn’t know that, and since it’s free anyway, they won’t cut it off when the bill stops getting paid. So there’s an e-mail address out there which is theoretically still valid, and someone could theoretically log in and check at any time… but they won’t. Does that count as “undeliverable” for purposes of this question, too?

Which raises a related question.

For such an abandoned free account, what legal, moral, or technical obligation if any does the email provider have to keep accepting mail on behalf of an account/address that never retrieves it? What’s common practice these days? e.g. If I had a free account that I last touched 5 years ago where the provider still exists today is my account probably shut down now? Or required by law to still be operational?

As always, Randall Munroe has long since written about something close to this: Facebook of the Dead. It’s even seasonally appropriate. :slight_smile:

The rule for hotmail/windows live/live.com free accounts is that after 270 days of inactivity it goes away. Saved mail, etc. is deleted and all future mail to that account bounces.

This is a notoriously harsh rule. Almost all others are much more forgiving.

I am sure that the email is not required by law to stay operational. At best you might be able to successfully sue them for not living up to the terms of service. But it would have to be a very poorly written terms of service that exposed the company to being sued for removing inactive accounts.

Gmail also reserves the right to delete accounts that go inactive for 9 mounts. I know from personal experience that in practice they don’t seem to delete inactive accounts.