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Category: Email Checker

What is Greylist

Last Update: 05.02.2019


During a list cleaning, you may have noticed a “Greylist verification in progress” icon. This icon informs you about a special email address detected on your list known as a greylist.

Greylist information

What is greylist?

Greylisting is an Anti-Spam safety precaution used by Mail Transfer Agents (MTAs) to protect email users from harmful spam.

Not every email cleaning service detects greylists.

How does it affect me?

Greylist verification lasts longer than usual since greylisted domains are temporarily blocked by Internet Service Providers. We wait for these ISPs to confirm if the email domain is legitimate.

Don’t worry.

If a greylist is found on your email list, it does not affect the results or speed of the remaining emails on your list.

You can download your other results at anytime while the greylist verification completes.