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How can I reject email from unwanted senders?


I keep receiving email from a source that I have never contacted. I do not want this to ever get onto my system. How can I configure my email to reject any item I receive from this source/email address?

The short answer is “it depends”.

It depends on your email provider, it depends on the email program you use, and it depends on the source of the email.

While I don’t know the specific answers for your situation, I can offer a few ideas and places to look.

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If you honestly mean that you never want the email to reach your system, then your only recourse is your email provider. Specifically, you’ll need to see if they provide you with any way to set up what’s called “blacklist”.

You may have heard of “whitelists” where you add email addresses that you know to always be valid. If your email provider supports it, email from addresses you place on your whitelist are never checked for spam.

Blacklists are the exact opposite. By placing an email address on your blacklist you’re telling your email provider to never accept email originating from that email address.

In other words, it sounds pretty much like exactly what you’re looking for.

There are two problems:

  • Not all email providers support blacklists. In fact, from what I’ve seen, few actually do.
  • Email rejected by being on a blacklist may generate a rejection message to the sender. You might not want that.
“By placing an email address on your blacklist you’re telling your email provider to never accept email originating from that email address.”

In either case, the only one who can answer the question of whether or not a blacklist is available to you, and how blacklist rejections are handled, is your email provider. Check with them.

Okay, so what if your email provider doesn’t provide blacklisting? Well, you’ll at least have to deal with the email in your email program. If you download your email, that means it’ll reach your system – sorry.

Some email programs actually provide the equivalent of blacklists in conjunction with spam filtering features, and that’s where I’d start. By adding the email address to your email program’s blacklist any email from that address will be routed directly to either the trash or your junk mail folder. In either case, you won’t have to see it.

Another approach is to use “Rules”. Rules are a feature of some email programs that allow you have the program automatically take action on email messages based on criteria that you specify. While they’re typically used for other things, in email programs that support this feature it should be fairly easy to say “if a message arrives coming from this email address, delete it”. Again, the result is that you should never see the message.

Your ISP doesn’t support blacklists, and your email program doesn’t support blacklists or rules?

Then you’re kind of stuck.

You could, I suppose, start marking email from that address as spam, but the problem is that over time that could cause other email – other legitimate email – to also start getting marked as spam. Probably not what you want.

In these cases, about all I can say is that the Delete key is your friend.

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11 comments on “How can I reject email from unwanted senders?”

  1. The easiest way by far to reject, delete, bounce Emails WHILE STILL WITH YOUR SERVER is to use a program called MAILWASHER, from
    The bounce function is really good as it tells the computer that sent the spam that your Email address does not exist.
    There used to be a basic free version that may be still be available on the web.

  2. The other method is the Block Sender option. Even though it does not guarantee it will never return under another subject line or the IP address will not be different which will allow it to pass thru it does keep most from coming back. I then take their IP address and add it to the Message Rules box.

  3. You can help stop spam by forwarding it to spam@UCE.COM and include a copy of the Message Source in the body of the forwarded e-mail. First you click on the ‘forward’ button, minimize the new e-mail page, RIGHT click on the original e-mail title in your inbox, click on Properties, click on ‘details, go down to the bottom and click on ‘message source’; highlight everything on the message source page, right click anywhere in the body of the highlighted message source information, click on copy, go back to your new e-mail that you are forwarding, click in the body of the e-mail message page, click ‘paste’ (all the info from the ‘message source should copy to the e-mail that you are going to forward), then ‘send’. This is a federal spam reporting site. You can also send the spam e-mails to the FTC but I don’t have those details handy right now. Hopefully, the UCE and the FTC will do something to stop a lot of these spammers.

    Hash: SHA1

    Roger: you’re assuming that people have “Block Sender” available to them. Not
    all do. In fact I dare say most do not.


    Version: GnuPG v1.4.7 (MingW32)


  5. I don’t understand why email can be recieved then deleted or blocked but cannot be rejected. Why can’t the email provider give us a “REJECT” or “Return to Sender” button? Why can’t it be rejected, sending it back exactly where it came from? Why can’t we jam the senders inbox with their own email returned.

    Because there wouldn’t be a point, and it would only clog up an already overloaded email system. Most spammers, for example, use fake return addresses, so your suggestion would “reject” email back to the wrong people.

    – Leo
  6. I use hotmail and would like to block and send blocked notice to sender (ex wife) so she knows she is blocked, not just have her messages automatically deleted. Is this possible?

    Not that I’m aware of.

    – Leo
  7. Bluebottle sends a email back to the sender telling them it was blocked as long as you have the person on your blocked list and lycos is another good one too.

  8. I keep getting the message [delivery notification]: failure, from a bank that was suppose to be processing a mortgage request for me. That started after I wrote the processor and told her they had terrible customer service. Is this a coincidence or could she block my IP address? The suggested articles don’t mention “delivery notification failure.” I think that witch knows how to do it.

  9. You answered that Hotmail just deletes the blocked email and doesn’t send a rejection reply. Is there a function under Outlook that will do it for a Hotmail account?

    You could certainly use message rules to set up auto-replies to certain incoming addresses.


  10. Your comment in response to the article (quoted below) is erroneous:

    “Because there wouldn’t be a point, and it would only clog up an already overloaded email system. Most spammers, for example, use fake return addresses, so your suggestion would “reject” email back to the wrong people.”

    There absolutely is a very legitimate point:
    You assume that this process is being intended only for spammers. Given circumstances for which that assumption is correct, I would agree with your response; however, for my particular purposes, that is an incorrect assumption.

    I am interested in rejecting / returning mail to one single individual for whom I know the address is valid / correct. It is essential that I achieve two things: 1) that I not accept delivery of the email; thus, simply deleting it is ineffective, because that would entail my accepting the email in order to delete it; 2) Also, it is essential that the sender know that I have not accepted delivery of the email. ideally, I would also be able to send an auto message to the sender indicating that the email has been rejected, unopened.

    This seems to be an issue for which a solution is in great demand. How is it then that no one seems to have stepped in to fill the vacuum?


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