Best we can say is: maybe.
Unfortunately, the answer is:
- Both
- Neither
- All of the above
Email-bounce messages are both annoying and informative. They can help you fix a problem with an email you've sent, or they can simply be another message in a big pile of spam.
Unfortunately, about the only thing you can count on is that you cannot count on bounce messages.
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Will email bounce?
Primarily due to spam, many email providers choose not to send bounce messages in response to email sent to bad addresses or closed accounts. Only if the recipient responds in some way can you know that the message has been delivered.
What's a bounce?
A "bounce" is an email message we get in response to an email we've sent that indicates our message was not delivered. Usually, though not always, the error message includes the original email.
The email you sent has not been delivered and is thought of as having been "bounced back" to you.
Hopefully, the error message contained in the bounce message tells you why it bounced -- but there are no guarantees.
What does "closed" mean?
I have to ask what you mean by a "closed" account in your question. It could mean many things, including:
- The user stopped using it. Email will be successfully received and accumulate. There's nothing here that would cause a bounce.
- The user could have "closed" the account but the ISP hasn't released or deleted it yet. Email may still accumulate without bouncing until cleanup happens after some period of time -- often weeks or months.
- The account existed but is now closed for some other reason. It still exists but is not accessible to its former owner.
- The account no longer exists.
- The account never existed.
While you might think of some of those states as being closed, not all of them will cause a bounce, and none of them require a bounce.
Email to a bad or closed address
Of the scenarios listed above, the one most likely to reliably generate a bounce is sending an email message to an account that never existed. The most common reason is that the email address was mistyped.
For all of the other "closed" scenarios, regardless of the reason, there's no predicting if email to that account will generate a bounce. Some services will under some conditions; others will not.
If you get a bounce, you'll know. If you don't get a bounce, it tells you nothing.
Bouncing spam
Many ISPs choose to ignore mail destined for invalid or closed destinations because of spam. Why? To avoid flooding the internet with even more noise.
You've probably received bounce messages for email you didn't send. Spammers have "spoofed" the email so it looks like it's coming from you and then blasted it out to anything they can find that looks like an email address. Some ISPs generate bounces if those addresses are invalid. Other ISPs don't generate bounces since they're as bogus as the spam that caused them.
The bottom line here is that an ISP may or may not return a bounce on an invalid email address (or on any error, for that matter).
But it gets worse.
Because so many bounce messages are the result of spam, even if a returning bounce message is the result of email you actually did send, some spam filters now filter those bounces out as spam.
So even if the recipient's email provider sends a bounce, there's no guarantee you'll get it!
What if I want a bounce?
If you want to close your account and want that closed account to bounce email messages being sent to it, you now know you can't count on that.
While technically not a bounce, the closest thing you can achieve is:
- Leave the account open.
- Configure an auto-response (out-of-office messages will do) that indicates the account is no longer monitored.
Ignore the account otherwise.
Note that this will not deter spammers. It's likely you won't care, though, since you're ignoring the account.
Do this
I will say this: most of the time, bounces work as you expect. The problem is, you can't count on it.
If you send an email to someone and don't get a bounce, that tells you nothing. They could have received the email or not. You can only tell if they reply or act on the information included in the message.
But if you hear and see nothing, you just can't tell whether or not the email arrived. (And of course, you certainly can't tell if they actually read it if it did. 
)
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If someone requests you to send an email to their address and it bounces, do they have any access to that in order to add a viris?
06-Oct-2010
I used a very old address to send a message & to ask a question. This address was at least 15 years old. If it is no longer a working address, will my message
still go or could it bounce back as not being available?
If you were sending “from” the address … it may well go through. But they’ll be unable to reply.
I tell you, closing a Yahoo! email address is such a massive headache. In the past, when I’ve closed other email accounts, email sent to those closed accounts has “bounced”. This is good, it means anyone I forgot to notify, will know that my old address is no longer working. It also means that I get the reassurance of knowing that the old address has been closed. Not so with Yahoo!
I followed the instructions to close my Yahoo! email account. I then sent a couple of test emails to my closed address, expecting them to “bounce”. They did not bounce. I then logged back into my closed address, I know that reopens the account but I had to look; sure enough my test emails were sitting in the inbox, they had not been bounced back to sender.
How long does it take before a closed Yahoo! email address starts bouncing messages? This is important to me so I would really like to know.
Because the Yahoo! way of dealing with closed accounts is so bad, it looks like I will have to re-open this unwanted account and monitor it for another 12 months, this seems to be the only way I can reassure myself that nothing important is slipping through. In my opinion this is not good enough and Yahoo!/Oath!/Verizon really need to review their policies in regard to email account closure,
My recommendation is to set up a vacation auto-responder in Yahoo! mail letting people know you no longer use the account, and then close the account and never login again.
I’ve always suggested never closing an account but keeping it open in case you get email from people you forgot to inform of the change. Your suggestion to set up a vacation responder message is great for that You can include your new email address in the message. You’ll still have to check that account periodically to keep it open, but if you only check it occasionally, the person writing you gets your new address right away.
A brief note – email used to include commands in the 1st line. 1 of those was for a return ‘receipt.’ On rare occasions, I see a prompt for a ‘receipt’ so maybe that still exists? IIRC, the commands line went unsupported several years ago in general.
Onto a new problem, SPAMHAUS. There are 2 email @ that bounce my mail from a mail.com id – all others work fine. I ran a deep virus scan and found nothing. The return msg seem to indicate the id is blocked by a whitelist. I was able to indirectly contact one of them thru someone who can reach the blocked ids. SPAMHAUS seems to be in the business of blocking email. There workaround lead me in circles until they asked for too much personal info and felt like phishing. What do you know about them? 1 failing id i on OUTLOOK.com, the other is on kanstellation.com Here is the latest return header:
nnnn@outlook.com:
SMTP error from remote server for MAIL FROM command, host: outlook-com.olc.protection.outlook.com (104.47.14.33) reason: 550 5.7.1 Service unavailable, Client host [82.165.159.130] blocked using
Spamhaus. To request removal from this list see https:[URL removed]
There are several blacklist (not whitelist) maintainers, and yes, it can be extremely difficult to get off of some of them. It’s quite frustrating at times.
Nice suggestion about using the “vacation” autoresponder to mimic a Mailer Daemon Bounce. BUT, you must ALWAYS set that autoresponder to send its message no more often than ONCE per day per recipient!
Otherwise, you stand a very good chance of creating a E-Mail Loop. Never a good thing!!!
That used to be a real problem, for sure. But most mail systems are really good at detecting and stopping accidental email loops, and they almost always build it into their auto-responders.