Can I stop or 'un-send' an email I sent by mistake?

When you hit Send...

When you hit the Send button, the following happens:

• If you're using a PC-based email program, like Outlook or Thunderbird, the email is sent from your machine to your email provider.

• The email is then send from your email provider to the email provider of your recipient.

• The email is then placed in the recipient's online inbox1.

• If the recipient is using a PC-based email program, he downloads it to his machine.

Two things are important to realize about that scenario:

• The first three steps – up to and including your recipients' online inbox – can often happen in seconds2.

• Regardless of which steps have and have not occurred, it's all out of your control once the sequence begins.

Once an email leaves your outbox, you lose all control over it. And I do mean all control over it. You cannot stop it. You cannot change it. You cannot track whether it's been read or not. You cannot tell if it's been forwarded or deleted. You can't even know whether it's been received at all unless you get some kind of response from the recipient.

Not really an exception: Gmail

Many people point to a feature in Gmail and tell me, "But, but ... Gmail lets you unsend!".

No. No, it does not.

Read the description of that feature (available in the "Labs" section of Gmail options). All that this feature does is delay the send for a few seconds. In other words, when you hit the Send button, Gmail doesn't send the mail.

At least, not right away.

After a few seconds, it does. And once it does send, then the Undo feature is no longer available for that message, because once email is actually sent, it cannot be un-sent.

All this feature does is give you a few seconds to change your mind. During that few seconds, the mail has not yet been sent.

An actual exception: Some corporate systems

"Corporate" here is really just a characterization because of course, these email systems could be used elsewhere. It's just more common to see them in large corporations.

Some of these email systems have a real, honest-to-goodness un-send option.

However, there are a couple of requirements:

• The sender and the recipient must both be on the same mail system. I'm not talking about Gmail or Hotmail or whatever, here. I mean that both sender and recipient likely work for the same company and use the same email system as provided by that company.

• The email has not yet been read by the recipient.

It's possible that an un-send function will actually remove your message from the inbox of the recipients.

The last item is hopefully obvious, but if they've read the message there's no way to make them un-read it. Once seen, it cannot be unseen. You might be able to "remove the evidence" in that perhaps the message might have disappeared from their inbox, but even then, they could have copied or printed it before that happened.

And again, this is not, not, NOT available with the email services available on the internet and not something that would work between differing email services even if it was.

An embarrassing exception: Recall

Some email programs and some email system expose a function called message recall.

The intent was – like Return Receipt – to provide a semi-standard way to "recall" or bring back a message that had been sent. In other words, a way to un-send it.

And much like Return Receipt, it's not implemented or it simply doesn't work as intended in most email programs.

When I've seen this attempted, the cure seems much worse than the disease.

The problem is simple: when recall is used, it works by sending another email message to all the recipients of the original message that says:

[Sender] would like to recall the message [Subject]

Now, I'm sure that the idea is that the message would never be seen by the recipients and that the mail programs would just recognize some special headers and perform the recall function by deleting the original message from the recipients inbox.

In practice, that's not what happens.

What usually happens instead is that everyone who got your first message by mistake now gets this second message drawing even more attention to the mistake.

I'm sure it works on some systems somewhere, but make darned sure you understand whether or not it won't just make people take special attention to your original mistake. Much like a politician attempting to delete evidence from the internet, there's a very good chance that all it really will do is make people take even more notice of whatever it is you're attempting to hide.

The moral of our story

There is no undo send.

Even if there were, you still run the risk of people reading the email before you hit Undo.

Once email is sent, you lose all control over it; all control.

Bottom line: make sure you really mean it when you hit Send.

(This is an update to an article originally published August 7, 2004.)