How to check whether email addresses are all valid or still exist quickly?

In my personal experiences, you always can have two ways to go on here:

1). Send a message to all of the email addresses.

As everyone mentions above, in this case, you can directly send a message to all of these addresses and see whether they are valid.

2). Apply a special email verifier to take chances.

If you think the first way is not so practical and efficient, you also can apply a special email verifier to take chances.

I have ever tried this free one named Dr Email Verifier:

http://www.email2verify.com

This verifier always can help easily check the validity of your entered email addresses in seconds. Moreover, its “Batch Mode” will also help check a batch of email addresses at once. What you need to do is only to import them rightly.

I hope this works for you.

On Wed, 25 Dec 2013 06:14:46 +0000, More08634timer wrote:

Recently, we have to send some invitation emails to some partners. However, a fraction of the recorded email addresses have not been used for a long time. We just cannot make sure whether all of them still exist. So, do you know any way for us to check whether all these email address are still valid or exist quickly? Thank you in advance!  

The only way to tell is the way you probably don't want to hear: send
a message to all of the addresses.

More

You might want to tell us which email system you are using.  There is not quick clean way other than by sending them emails.