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If I Send to a Bad Email Address, Will Someone See It?

And what can you do about it if they do?


People often send email to the wrong address by mistake. But what happens if the email address is invalid?
Question: I just sent an email to the wrong email address. I am positive that the email I sent it to was wrong, as I read it once it left and it asked if I wanted to add it to my contacts after I sent it! I am 100% certain that there is no one at work with that address. Please tell me where it could possibly have gone and is someone going to be able to read it??? I am really worried as it was quite personal.

Someone may see it. Someone may not. There’s just no way to know unless someone replies to tell you they did.

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Email sent to the wrong address

Once you send an email to what you discover is an incorrect email address, there is nothing you can do. Someone may or may not read it. You may or may not find out about it.

Sending to a bad email address

Depending on what was wrong with the email address and the configuration of the email system, many things could happen to your misdirected email.

  • You may get a bounce telling you the message was undeliverable. This is the best situation: you’d know it wasn’t delivered to anyone.
  • It may be silently discarded. No human may ever see it, but you wouldn’t get any notification.
  • It may have been forwarded to a “catch-all” mail address. Many email servers forward email sent to an invalid address to one central address. The idea is someone would decide if it was meant for someone else and forward it. Thanks to spam, this technique is extremely rare these days, but it could happen. You may or may not get a notification.
  • The bad address may be valid. I know you said you’re 100% sure, but how can you really be sure? Your typo could result in someone else’s valid email address. They may or may not see the message, and they may or may not respond.

Remember that system administrators can see all email, valid or not. Whether they do is unknown, but they could.

The bottom line: someone might see it. Or not. There’s just no way to know.

Do this

Once you hit Send, you lose all control of email.1 There is nothing you can do to recall, un-send, or otherwise prevent whatever happens next from happening.

What you choose to do next depends on the situation and your message. Perhaps you need to explain to the unintended recipient. Perhaps you need to apologize. Perhaps you need to start looking for a new job.

More likely, you need do nothing until you hear that the message was in fact seen by someone.

Podcast audio


Footnotes & References

1: Even “undo send”, available in some email programs, lies. It merely delays sending for a few seconds.

25 comments on “If I Send to a Bad Email Address, Will Someone See It?”

  1. Depending on the contents of the original e-mail, you could always follow up the same wrong address with a simple message along the lines of: “Sorry for the confusion. I mistyped the e-mail address, and it wasn’t meant for you.”

    If the address happens to be “live”, or ends up in a catch-all box, the recipient will at least understand why they got this message. (And if it bounces, or goes to the bit-bucket, the same fate will meet the second message, and no harm is done.)

    Of course, if the original message was something that you wouldn’t want someone at work seeing, you’re on your own. :-)

  2. Thanks so much for your replies… i feel a little better knowing that there is a high chance that it wont even be read at all…

    Just have to leave it up to the Gods now…

    Only hope that karma is on my side

    thanks again :)

  3. This should be a lesson learned…do not ever, EVER, send something personal to a work/business E-mail account. That is what personal E-mail is for. Business E-mail is subject to being looked at by the admins. So, if it was personal, it could be seen, even if it does go to the intended party. Sorry if I seem “preachy”.

  4. I had this experience: I mistyped an email address causing me to inadvertently send an email intended for my ladyfriend who lived 30 miles from me in CA, to a married lady living in New Zealand. I did not realize my error until I received a response asking : Do I know you? I wrote back explaining the situation and recipient and I have become sort of pen pals.

  5. I am trying to send a HUGE invite from youtube. So I gathered all my contacts into one word doc, separated them by commas and cut and pasted it into my youtube address box and pressed send. An error message came up saying please list valid address. Is there a quick way to find out which addresses are invalide?

    Hash: SHA1

    My guess would be that you’re exceeding a limit … it looks like there’s a 200
    character limit.

    Version: GnuPG v1.4.6 (MingW32)


  7. If you want to know if anyone read it, send a followup email explaining the mix-up and then earnestly ask the receipient for their advice about a related problem.
    If they got the first email, they will reply.

  8. Dear Leo, For last few days, I am experiencing a problem that I receive email from Mailer-Daemon that contains below message. and more annoying point is, that address is unknown for me, means i did not send email to that email address. Please guide, how my outlook is sending to an unknown email address.

    I’m sorry to have to inform you that your message could not be delivered to one or more recipients. It’s attached below.

    For further assistance, please send mail to postmaster.

    If you do so, please include this problem report. You can delete your own text from the attached returned message.

  9. I send out regular ‘eblasts’ to our members and in one of them I typed in the wrong email for them to respond to. I realized the error and the next week I changed that email to the correct one. However, the paragraph with the email was one I simply cut and pasted into the new eblast. Even though I changed the email within that paragraph, I discovered, some weeks later, unfortunately, that members were clicking on the ‘correct’ email but being sent to the incorrect one. I have since typed that paragraph from scratch and the problem is solved. But I’m wondering – why did that happen? It has caused me some real headaches.

  10. Gmail now allows you to set an “unsend” time of up to 30 seconds. Still pretty quick but no harm in setting it up that way so you have a few moments after the realization to take action.

    From Google:

    -On your computer, go to
    – Be sure you are logged in to the correct account
    -In the top right, click Settings Settings and then See all settings.
    -Next to “Undo Send,” select a Send cancellation period of 5, 10, 20, or 30 seconds.

  11. Think of hitting the Send button as dropping a letter in the mailbox. Once the letter is in the mailbox, you just can’t retrieve it.
    With an E-mail, it’s the same, just faster.


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