Verify ifthe email address exist

Question

User2070555482 posted

Hi guys I'am maintaining the legacy web which is asp.net web form using VB, and i dont know how to validate or verify an email if its a real account.

Hope you may help me thank you

Answer 1

User753101303 posted

Hi,

The usual approach is to send a mail with a unique clickable link so that you can confirm that someone received the mail and clicked this link.

You'll perhaps have a suggestion about testing against the mail server but not all servers are allowing that (so you have so to speak a "yes" or "don't know" response but you'll never be able to tell that a mail address really doesn't exists at all).

Answer 2

User-893317190 posted

Hi TinVin727,

As PatriceSc  has said , there is no direct way to know whether an e-mail address exists.

As an alternative, you could verify the syntax of  the e-mail address.

Use the MailAddress's constructor  to help or  use regex.

Please refer to the link below https://stackoverflow.com/questions/5342375/regex-email-validation

You could also refer the next link  https://stackoverflow.com/questions/3883518/can-i-check-if-an-email-address-exists-using-net

Best regards,

Ackerly Xu

Answer 3

User61956409 posted

Hi TinVin727,

Firstly, you can try the approaches that PatriceSc and Ackerly Xu shared to valid email address format via regex and detect if user is active. 

Besides, as far as I know, some email checker REST API (such as https://github.com/trumail/trumail) can help measure email deliverability and quality, you can search about "email checker rest api" in your browser and know how to use it to validate an email address.

Note: the APIs might not be free, before you use it please read pricing details. 

With Regards,

Fei Han