Email Verification

I am trying to clean my email newsletter list by deleting addresses that no longer exist. I purchased Atomic Verifier and MaxProg Verifier. I have even used an online verification system. But still, I find bad emails in my list. Is there an email verification program or site that does a good job cleaning lists without costing me a fortune? Thanks.

The only certain way to verify a destination email address is to send an email via authenticated SMTP to that address and see if it bounces back. Any email sent any other way may simply be blackholed by the recipient mail server in order to ensure that spammers can’t tell if the email address exists or not. For the same reason the SMTP verify command is often disabled on mail servers so as to prevent being able to check if an address exists without actually sending an email.

Any validation system that doesn’t actually send authenticated emails and test for bounces will only be able to identify some of the email addresses as invalid as any properly configured mail server will simply not provide any information on whether or not an email address exists unless it is trying to deliver an authenticated email.

Thank you for your response. So, what you are saying is that unless a verification program actually sends a message and checks for bounces, they may not be very effective in capturing non-existent emails. Unfortunately, this defeats the purpose as I would like to capture these emails before conducting a newsletter campaign so that my IP reputation isn’t negatively affected by bounced emails.

You can thank spam for your situation. It would be an absolute nightmare for the end users if anyone could verify the validity of email addresses without them opening an email.

The best you can do is to make sure that you only ever get one bounce per email address.

To avoid having all the bouces occur at once when you actually send an email you should use a double opt-in list where the sign ups get sent an email immediately and have to click a link in the email in order to complete the sign up process. That way either the confirmation email with the link will either be blackholed or bounce and only those emails that actually exist will be added to the mailing list.

Without double opt-in working like this you have no way to prove that the person actually signed up (which makes your emails spam by definition under Australian law at least - the USA has different laws to actually encourage spam).

I agree with the double opt-in. But this is only effective in the short term. If someone signed up a while back, they may no longer own that email address and I am back to square one.

Are you basically stating that all of the verification products and online verification systems are incapable of capturing nonexistent email addresses? To my knowledge, none of them guarantee 100% accuracy. However, they usually stand by 70 to 80%.

That would indicate that 70 to 80% of the email servers are still wide open to spammers and don’t have proper protection built in. The figures they are quoting are probably from several years ago as the number of open mail servers is a lot lower now than it used to be.

Remember that spammers can use this software and feed in huge lists of possible email addresses trying to find ones to send spam to.

As for long term list members - the next time you send out an email using SMTP you’d get a bounce and would then know that the address is no longer valid and can be removed.

If I send emails frequently, deleting bounced messages per send would make sense. However, I don’t send emails that frequently making bounced messages from emails that no longer exist a real problem. Sending emails that bounce can get me blocked by my ISP. That is why I feel that it is important to attempt to clean the list the best I can before an email campaign to prevent ISP issues. It is amazing to me that with all of our technology, there isn’t a reliable method to determine if emails are bad!

Only by sending an email using authenticated SMTP and seeing if it bounces. Sending an email any other way will likely just be blackholed if the receiving address doesn’t exist so as to not advertise whether the address exists or not to spammers.

It used to be possible to tell whether an email address exists or not without sending an email to it but spammers made up over 98% of the people using those facilities so they were turned off.

Unfortunately, this defeats the purpose as I would like to clean the list before emailing so that I don’t experience problems.

You could at least verify that the address meets the RFC spec - if - you can find a good regex - the RFC is complicated and I’ve yet to find a regex I feel totally confident with.

True, this wouldn’t ensure than an email address is real, but it would be a start.

Surely the double opt-in to the list in the first place confirms that not only the address is a possibly valid one but that it actually exists and belongs to the person who signed up at the time of the signup.

The address isn’t suddenly going to fail to meet the RFC spec at a later date just because the person closed that email account.

True, and I agree double opt-in is the way to do this. For some reason I got the impression others had problems with this

It would be amazing to me that no one bothers to clean their list before conducting an email campaign. All I want to know is what can be used to clean lists that is somewhat reliable in distinguishing between good and bad emails.

Why? It seems it easier to leave the list as it is.
You have been given reasons why it is difficult if not impossible to check, yet you carry on with the same question.

If you want to tidy up your list send out an email saying “do you want to continue to receive my newsletters” and if the respondent does he will get back to you. I bet you will get a very limited amount of replies - not because you newsletter may be good or bad but most people are very lethargic.
This will still not prove a valid email address or not but will give you a list of people wanting to recive your newsletter which brings us back to the start and just send it to everyone you have listed anyway.

That is because my question was really never answered! There are a zillion services and software out there designed to clean lists. But no one from this forum will recommend any one. Basically, I am getting from this forum that none of them actually work. The only recommendation I received was to remove bounced emails after they bounce which basically defeats the purpose. I would like to prevent the bounces by removing the emails before sending the emails.

How could any software know if an email address is active or not without testing it?

IMHO, your best option is to use a service like CampaignMonitor or MailChimp. Sending out a big campaign is cheap, if not free, and their inbuilt tools filter out email addresses that prove to be outdated after each send.

That also gets around any issue with your ISP, because it has nothing to do with them.

That is why I am seeking various opinions regarding this issue on the forum!

I considered using those online mailing services. However, I would prefer sending emails on my own. Also, it is my understanding that these services can suspend or terminate services if there are too many bounced messages which again, defeats the purpose.

I am actually looking for recommendations from those that actually used a specific service or software that cleans email lists. I understand that some from this forum may feel that these services/software are not reliable. However, I would like the opinion of others as well.

Any that do not actually send emails and check for bounces have absolutely no way of telling whether a given email address exists or not. All they can do is guess.

So what you are asking is which service does the best job of guessing which email addresses don’t exist without any real data to base their guess on.

All of the above responses are based on how email actually works. Presumably those creating software to clean up address lists without sending emails are written by people who don’t understand how email works as all of the other ways of telling were being abused so much by spammers that most legitimate sites now have them turned off. Any program relying on those methods to clean up the list would likely remove the real email addresses for anyone who is using a server that is using proper authentication - as their server will not respond to anything but an actual email - and will leave all the junk email addresses from servers that haven’t quite gone that far as those don’t produce bounces for any email address regardless of whether it exists or not. Exactly which do what would depend on which particular method of guessing that the service uses but by definition none of them can do it accurately without actually sending authenticated emails.

I would expect that randomly deleting 80% of the email addresses from your list will be as accurate as any of the services that say they have an 80% accuracy rate.