Blocking email

This is when someone blocks your email and you get a message from mailer daemon.

If you try to send from another email account and it is also blocked, when you had never sent an email from that address before how did that occur? Does the blocking work by blocking the whole computer machine?

I never have blocked anyone myself. How does it work?

It could be your IP. It could be a block of IPs you just happen to be in. It could be your domain. It could be something within your email causing problems. It’s not likely to be related to your specific machine unless it has a virus and has been sending out enough emails that other domains are blocking it (like hundreds or thousands per hour).

The email response you get may have some hints as to what the problem is.

If you can send an email via your phone, try it that way. If it’s still blocked, take the phone off wifi (so it’s using data through your carrier) and try again. If that works, it’s something to do with your IP address. If it’s still blocked, it’s somehow related to you.

I had an issue like that years ago and ended up having to sort out some MX record stuff.

Also note that it may not be an intentional blocking. In fact, if they were doing it because they didn’t want to hear from you, it would seem weird to let you know about it, rather than just automatically trashing it. Letting you know suggests they want legitimate emailers to know there is something wrong and try to fix it.

And one thing that occurred to me: does your email contain an attachment? Those can be a reason an email gets blocked. It could be a not-allowed file, too big, or they may just block all attachments.

Well this has happened twice and by the context I know that both times the recipient is trying to block me. They are a couple of long stories.

I don’t understand. What do you mean automatically trashing? Just throwing it out?

When you get a mailer daemon as “permanent error” I have to assume you are blocked.

Why wouldn’t the person want you to know you are blocked if they want to block you?

I meant automatically deleting it. I called it “trashing” because technically it usually goes into a “trash” folder, so you can recover it if you need to. That’s usually how you deal with messages you don’t want to receive. (I do it for certain publications who won’t let me unsubscribe, for instance.)

And letting someone know you’ve blocked them allows them to now try to find away around that block. There’s not really anything in email preventing that. So I’d generally consider it a bad idea if you were blocking someone because you dislike them or how they act.

If you’re just getting the “permanent error,” that can mean a lot of things. It can even mean that the email address where you sent the message doesn’t actually exist. That is, in fact, the most common reason, in my experience. Another is that the email address is outward-facing only.

If nothing in the daemon’s reply mentions that your email address is being blocked, I would not assume that is the issue.

Do you know how to block someone and what is supposed to happen when one does?

Still not sure how to analyze it when it shows as permanent error.

And I’m pretty sure I’m being blocked. I think they want me to know I’m blocked.

I get that the address might be invalid but there is no indication of a change for this person and the address is on the net as a professional address. Was using it for decades.

It is possible that the recipient’s mailer is spoofing a mail daemon error. You should be able to tell by carefully looking through the header.

For the mail daemon to generate the error itself the blocking rules would need to be in the config file for the daemon, which isn’t exactly easy or likely.

If it is the recipient’s mailer doing the work setting it up is of course easy. Otherwise there would need to be rules detecting mail from you in the delivery chain. Rules could look for your name in the email body, or any other identifying mark. It need not be done by sender address.

You mean the message permanent error? There’s not much else to it.

The recipient is at a large university. Maybe my name is detected and they have used the admin capability to block me? How likely is it that a university employee can get access to the admin and block me with rules about names?

I still don’t know if blocking is something people even can do and what the outcome is if not a mailer-deamon permanent error.

It is also possible that if you are using a small email service, large organizations sometimes block that entire domain due to large amounts of spam from that domain. The fact that it results in innocent people being blocked is a price some big boys are willing to pay.
In your case it sounds like the best thing to do is to contact the recipient or their email provider (say the company receiving the email) and inquire whether it is their problem or yours. As has been said, if the individual wanted to not receive emails from you, it is far easier to just create a rule that moves all your emails to the trash. Doing more than that is more work than necessary.

This is an automatically generated Delivery Status Notification.

Delivery to the following recipients failed permanently:

  • [

Reason: Permanent Error

I interpret that as a bad or non-existent email address. Make sure the email address you are using is valid. That message says it isn’t.

The error message need not be real.

A simple trick is this:

Possibly because they’re ghosting you.

Well of course theyre doing that.

Interesting. I think it was instantaneous though. I don’t think there was time to do that.

Delivery has failed to these recipients or distribution lists: Server “” returned an error: * [email address]: 550 5.2.1 The email account that you tried to reach is disabled. Learn more at 5.2.1 Fix bounced or rejected emails - Gmail Help s9-20020a17090302c900b00153b2d165bfsi9580310plk.455 - gsmtp

Hard. But it is all software, so all things are possible.
Like I wrote above, the error message might only appear to come from the mailer daemon. You are just reading a bit of text that says it came from it. Trivially spoofed. The headers would show the truth of the matter.

An institution could offer a blocking service as part of its mail infrastructure. In a university that might be a good thing to do. All manner of bad behaviour can occur, and offering staff and students a centralised blocking service could be sensible thing. How that blocking looks is an open question. A permanent error message is a good way of getting people to stop trying.

Well I tried from two addresses that are very common and they both came back instantly. It would have to be a programmed spoof.

Automation of a fake mail failure can be done in the recipient’s mailer.

For instance: