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Check If Email Exists

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71–80 of 260 posts

Re: Check If Email Exists

#71

My email address reachability is "unknown", its a fastmail hosted account. Quite a commonly used service. Is an unknown classification supposed to be treated as "I don't know, probably safe" or "I don't know, probably don't accept it" ?

{ "input": "***redacted***", "is_reachable": "unknown", "misc": { "is_disposable": false, "is_role_account": false }, "mx": { "accepts_mail": true, "records": [ "in2-smtp.messagingengine.com.", "in1-smtp.messagingengine.com." ] }, "smtp": { "error": { "type": "TimeoutError", "message": "future has timed out" } }, "syntax": { "address": "***redacted***", "domain": "***redacted***", "is_valid_syntax": true, "username":…

I also get "unknown" for my Zoho Mail addresses; also a pretty popular provider.

    {
      "input": "***redacted***",
      "is_reachable": "unknown",
      "misc": {
        "is_disposable": false,
        "is_role_account": false
      },
      "mx": {
        "accepts_mail": true,
        "records": [
          "mx.zoho.com.",
          "mx2.zoho.com."
        ]
      },
      "smtp": {
        "error": {
          "type": "SmtpError",
          "message": "permanent: 5.7.1 Email cannot be delivered. Reason: Email detected as Spam by spam filters. "
        }
      },
      "syntax": {
        "address": "***redacted***",
        "domain": "***redacted***",
        "is_valid_syntax": true,
        "username": "***redacted***"
      }
    }

Re: Check If Email Exists

#72

Earlier quoted context omitted.

Would you mind sharing your experience on how well that has worked for you? Has the complexity of maintaining different addresses been a problem? I ask because it is something I have always thought about, but I suppose I kept hoping a service would come along and magic the solution for me. Kudos on making it happen!

I did it for ages and eventually stopped. It gets awkward when you have to deal with customer support people and I never caught any spammers via the method anyway. Difficulty wise it was trivial since all emails hit my main address.

When I can tell it'll be awkward, I just make up some letters on the spot like "gj5@mydomain.com". It's easy enough to look for To:gj5 in your horded mail to find out what business it was.

Re: Check If Email Exists

#74
post #32

If I were to self-host this (for instance to validate order emails and catch typos on a moderately visited e-commerce website, in the order of hundreds per day), what are the odds that I'll be banned by the major email providers (gmail, hotmail and co.) for abusing their servers?

You'll get blocked by your hosting provider first. See a recent instance here: https://www.lowendtalk.com/discussion/comment/3237390/#Comme...

Re: Check If Email Exists

#75

Earlier quoted context omitted.

Would you mind sharing your experience on how well that has worked for you? Has the complexity of maintaining different addresses been a problem? I ask because it is something I have always thought about, but I suppose I kept hoping a service would come along and magic the solution for me. Kudos on making it happen!

I'm not OP but I do something similar, which I can describe. I don't whitelist addresses, I have a domain with a catchall account. So I make up addresses as needed. When I want them to die, I add them to a ruleset on the server that punts them into the bit bucket. So far it has been really great. Easy, effective. Edit: Like the other reply you got, I use FastMail for this service.

I do something similar and also use FastMail. I use @sites. for all site signups, eg news.ycombinator.com@sites.example.com

Re: Check If Email Exists

#77

Earlier quoted context omitted.

Would you mind sharing your experience on how well that has worked for you? Has the complexity of maintaining different addresses been a problem? I ask because it is something I have always thought about, but I suppose I kept hoping a service would come along and magic the solution for me. Kudos on making it happen!

There is a service for that: https://anonaddy.com/ I've used it briefly for testing purposes and I have no complaints about it, it delivered what I expected with no hiccups.

Adding another comparable offering is https://simplelogin.io and you can set a PGP key for forwarded emails.

Re: Check If Email Exists

#78

Earlier quoted context omitted.

I specifically bought a cheap .org since some companies have trouble with lesser known TLDs

I have a .red and a .me and I have never not been able to sign up.

.life has four letters. Lots of terrible attempts to validate email addresses reject TLDs that aren't 2 or 3 characters.

Re: Check If Email Exists

#79
post #8

Could someone spell out a use case for this? One that comes to mind would be validating that a mailing list doesn't have any outdated email addresses in it, but couldn't that be determined by just checking for a bounce when a message is sent to it? I tried to sign up for SiriusXM the other day, and though I could create an account with my .pro email address, I couldn't actually sign up for service with that same addr…

I just watched a video where someone demo’d GitHub Copilot by writing a comment along the lines of // IsValidEmail takes a string and returns whether it’s a valid email address The AI response was a nightmarish 100+ character regex that made my blood curdle. I think of email validation like encryption: don’t roll your own, and don’t trust an AI to do it either. Edit: Here's the regex: https://gist.github.com/cassidoo…

100+ is nothing.

This is a regex that validates a string against the RFC822 "Standard for ARPA Internet Text Messages" and it contains 6424 characters.

http://www.ex-parrot.com/~pdw/Mail-RFC822-Address.html

Re: Check If Email Exists

#80
post #48
post #8

Could someone spell out a use case for this? One that comes to mind would be validating that a mailing list doesn't have any outdated email addresses in it, but couldn't that be determined by just checking for a bounce when a message is sent to it? I tried to sign up for SiriusXM the other day, and though I could create an account with my .pro email address, I couldn't actually sign up for service with that same addr…

The use case is marketing email. Sending to non-existent addresses can radically affect deliverability. If the address is to a large host, then they will use reaching invalid email addresses as evidence that you are not keeping to best practices. They will throttle deliverability, and possibly reject email. If your sending to an invalid host, then your mail sending provider (if your using one) may consider you a bad…

Any engineer or product team that uses this lacks ethics and is putting their company at risk for CANSPAM.

If you work at a company that would abuse hibp and a direct mention in CANSPAM you should refuse the work.

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