Show HN: Check whether an email address exists
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Show HN: Check whether an email address exists
1–10 of 20 posts
Re: Show HN: Check whether an email address exists
#2A link to an "how it works" article would be nice.
Re: Show HN: Check whether an email address exists
#3This is cool but yea some right up would be appreciated.
Re: Show HN: Check whether an email address exists
#4Not working reliantly for me. Addresses that definitely exist are reported as not existing. No info on the checks used.
So, this could even just be a clever way to collect email addresses through a simple form.
Re: Show HN: Check whether an email address exists
#5Nope. Reports @example.[something] as existing, whereas info@[something else] - which regularly gets mail - as nonexisting. Both Type I and Type II failures, but confidently proclaims the verdict? Worse than useless: actively misleading.
Re: Show HN: Check whether an email address exists
#6A link to an "how it works" article would be nice.
Apparently tries to resolve MX, connect and try to poke around. Surprisingly, the last time that trick worked reliably was in the early 2000s, because guess who also used the same trick? Yup, spammers - so most servers will either a) deny existence for any address, or b) claim existence for every address. And that's before greylisting and SPF and whatnot.
The only way to be sure that the address actually exists is to send mail and have the recipient actively respond - however, if there's no response, it can mean any number of things: no such address, message got lost, message got spambinned, message got deleted by recipient, recipient couldn't be bothered to reply.
In other words, do not expect certainty from e-mail.
Re: Show HN: Check whether an email address exists
#7Heh, we all learned to disable VRFY 15-20 years ago.
This fails both ways on my tests.
Re: Show HN: Check whether an email address exists
#8It seems that some domains just kill the backend. For my work e-mail, and probably any other on the same domain, it returns HTTP 503 (service unavailable) after ~30s, and frontend is stuck at "Checking…" forever. Maybe our mailserver fights back the spammers somehow. :)
Also, it kinda sucks that i can't send the query with Enter key, and i bet it sucks much more for eg. visually impaired users. Is there any particular reason you used bunch of s instead of good old ?
Re: Show HN: Check whether an email address exists
#9We use Cisco's cloud Ironport solution for email spam protection and I get the following when I check my email address:
Error: Invalid greeting from server - XXXXXXXXX.iphmx.com 554 Your access to this mail system has been rejected due to the sending MTA's poor reputation. If you believe that this failure is in error, please contact the intended recipient via alternate means.
Re: Show HN: Check whether an email address exists
#10Um... I hate to be so harsh but this is worthless. Checking a few of mine, all different domains, I got
Nemesis ESMTP Service not available 554-No SMTP service 554-IP address is black listed.
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This domain has a catch all email address so we are unable to determine if this email matches an account.
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Error: Invalid greeting from server - 554 No SMTPd here This email does not exist or cannot be found
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Error: Invalid greeting from server - 554 Your access to this mail system has been rejected due to the sending MTA's poor reputation. If you believe that this failure is in error, please contact XXXXXX This email does not exist or cannot be found
So... yeah... 100% error rate on something that says "the results should be relatively trustworthy." Relative to what? That success rate doesn't even crack the Mendoza Line.