Is there any way I can keep from letting people forward emails I have sent them onto others?
In short: no.
And it can get even worse. Much worse.
•
Once you've sent email, it's gone and you lose all control over it. And by all control, I mean:
- You cannot "un" send it, or prevent the recipients from getting and reading it.
- You cannot reliably tell whether or not the recipients have received it.
- You cannot reliably tell if the recipients have read it, deleted it or forwarded it.
- You cannot prevent them from forwarding it, copying it, changing it, or doing pretty much whatever they want with it.
Note I said "reliably" in a couple of cases. There are technologies, such as "bugs" or simple image tracking for HTML formatted email, that can sometimes allow you to tell that an email has been opened. This is not 100% accurate, and hence cannot be absolutely relied on, mostly because modern mail clients often have the required functionality turned off by default as a security and privacy measure. And "opening" an email does not necessarily mean that the email was actually read or even seen by anyone.
But in regards to your question, it's the last one that should causes us all to think.
I'll put it more clearly: you cannot prevent someone from forwarding your email, and you also can't prevent them from changing it before they do so.
Get that? Not only can the forward your email, but they can change what your email says. When someone forwards an email, that email simply becomes the body of a new email, that can be edited before hitting send. And by edited, it could be as simple as changing a "yes" to a "no", an "I love you" to a "get out of my life", or perhaps "the boss is a genius" to "the boss is an idiot".
You get the idea. If you were concerned about your email being forwarded, you can be even more concerned now. You really do need to trust your recipients.
So, if email is such an unreliable medium, what can you do? Well, the simplest first step for this particular issue is to save all your outgoing email. That way you'll have a record of what you really said. Second, don't say anything in email that you wouldn't want to be made public, and when things get "close", make sure you're only emailing it to someone you really trust.
There are technologies such as cryptographic message signing that will allow message tampering to be detected, but currently they're used mostly only by some businesses and the tech savvy. To be honest it shocks me how much sensitive information is transmitted in email without any protection whatsoever (other than the silly disclaimer that boils down to "if this message wasn't intended for you, forget everything you just read").
I'm hopeful that over time these types of security solutions will get easier, and more common.
And the bottom line is that if someone can read your email, they can still forward it, or copy/paste it to another email, and send it to anyone they choose, one way or another.
Related:
-
Ask Leo! - Can I stop or 'un-send' an email I sent by mistake?
-
Ask Leo! - Can I tell if email I sent has been read by the recipient?
-
Ask Leo! - How do I get a notification when anyone I send an email to forwards that email?
Article C2509 - January 3, 2006
Someone keeps hacking my email and then giving my password back. So that I'm able to use my email and then at other times I'm not. Can you tell me how to make my hotmail secure so that the hacker cannot hack it again? Please reply quickly before the hacker hacks my email again!
Posted by: Nora at March 25, 2007 8:09 AMI read the article and comments, but nothing seems close to what happened to me. This is everyone's worst nightmare: My ENTIRE hotmail account of 1,600 e-mail messages (received since 2003) was somehow recently sent to a friend's PC! I was working on another friend's computer sending out notices of an upcoming event. Oddly,here was no reply button, so I sent each individual an email by going to file and send. A weird box came up that warned of either a virus or worm, but also stated it could mean I was simply sending out repeated text. The warning asked if I still wanted to send (which I did, as much of the text was indeed repeated text of the same event). Soon thereafter, three of my friends reported receiving emails from the owner of the PC with strange attachments. The owner, an honest person, denys this. As mentioned, only one of these friends (boyfriend) also received my WHOLE email account with access to all my private mail! Does it sound as if my account was hacked into, or the PC I was using, or perhaps the PC of the recepient of my 1,6000 private emails? Needless to say this is a nightmare. Is there any possiblity the receiver of these e-mails could even be responsible? How do I find out? Who should I report this to? My privacy was grossly violated! Thanks.
Posted by: Marie at May 15, 2007 2:03 AMI recently received a spoof email that I can NOT forward to the spoofed bank's investigation section or anyone else (not even to myself). I can forward any other message to anyone I like. What's going on?
Posted by: Herb R at January 10, 2008 9:59 AM-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
No way to know without more details of how it's failing.
Thanks,
Leo
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (MingW32)
iD8DBQFHh6tTCMEe9B/8oqERAvvjAKCLkwyv6OoiC7MiwpsY3n5De1PPiACeLKA4
Posted by: Leo A. Notenboom at January 11, 2008 9:45 AMgZglzdO8ThuUns6Mc1mhp2o=
=upyi
-----END PGP SIGNATURE-----
I concur 110% w/ Leo... Tried a few methods offered directly by MS for Outlook 2003 & Outlook 2007. Neither was even close to being foolproof, even when sending to another person internally. As mentioned all too often - once the message leaves your server, ALL BETS ARE OFF. Someone out there is going to find a way to copy and/ or forward your message.
Posted by: stan at November 20, 2008 4:42 PMIn our business we type sensitive messages and output them as attached PDF's. As they are image type PDF's it makes it a bit more difficult to tamper with.
Posted by: Gordon at January 21, 2009 9:01 AMWhy do I keep getting my aunt's email sent to my account when they are sperate?
Posted by: Tina at February 8, 2009 8:49 PMLotus Notes does indeed prevents copying. We use it at Office and have found it works ! Leo- what comments ?
19-Jul-2009
Posted by: Heshan Fernando at July 19, 2009 6:40 AM
Hi,It is possible to make sure your mail is not forwarded provided you are using outlook.But if you are using yahoo or gmail,it is not possibe
30-Aug-2009
Posted by: Mohana at August 30, 2009 8:25 AM
I wanted to answer the question being asked about regarding forwarding emails. There is a way in Outlook 2007 on preventing the email from being forwarded. I was not sure if this question is being asked of a previous version or not. In Outlook 2007, the instructions are below. I recall in Lotus years ago the ability to stop forwarding as well as printing of the email.
Open and create the message,
Click the Office Button,
Go to Permission and click Do Not Forward
In Outlook 2003, you would have to create a Form and the problem with this is that both the sender and receipient would both have to be using Outlook.
Posted by: LaTonya Blount at October 26, 2009 11:28 AM