bounce, it is safe to assume* that the address is real.
catch-all email address meaning that messages addressed to a non-existent mailbox will not be returned to the sender but in most cases, such email messages will bounce.
4
When you send an email to someone, the message goes to an SMTP server which then looks for the MX (Mail Exchange) records of the email recipient's domain.
For instance, when you send an email to hello@gmail.com, the mail server will try to find the MX records for the gmail.com domain. If the records exist, the next step would be to determine whether that email username (hello in our example) is present or not.
Using a similar logic, we can verify an email address from the computer without actually sending a test message. Here's how:
Let say that we want to verify if the address billgates@gmail.com exists or not?
Ed. note: Amit details a few Windows-specific tips, but this method should work across platforms.
telnet in Windows. Or if you already have the PuTTY utility, skip this step.
8
nslookup –type=mx gmail.com
This command will extract and list the MX records of a domain as shown below. Replace gmail.com with the domain of the email address that you are trying to verify.
gmail.com MX preference=30, exchanger = alt3.gmail-smtp-in.l.google.com gmail.com MX preference=20, exchanger = alt2.gmail-smtp-in.l.google.com gmail.com MX preference=5, exchanger = gmail-smtp-in.l.google.com gmail.com MX preference=10, exchanger = alt1.gmail-smtp-in.l.google.com gmail.com MX preference=40, exchanger = alt4.gmail-smtp-in.l.google.com
For that, go to a command prompt window and type the following commands in the listed sequence:
3a: Connect to the mail server:
telnet gmail-smtp-in.l.google.com 25
3b: Say hello to the other server
HELO
3c: Identify yourself with some fictitious email address
mail from:<labnol@labnol.org>
3d: Type the recipient's email address that you are trying to verify:
rcpt to:<billgates@gmail.com>
- abc@gmail.com — The email account that you tried to reach does not exist.
- support@gmail.com — The email account that you tried to reach is disabled.
reverse email search to find the person behind the address. And if you get stuck somewhere, this step-by-step video should help:
ps:国外在线邮箱验证网址：
http://lightinemails.com/emails/VerifyEmails.aspx
http://verify-email.org/