A Domain Name System Blacklist (DNSBL) is a list that allows internet service providers (ISP) and other website administrators to block emails or traffic from specific systems. It's usually those that are known for sending spam and other malicious content. Normally, a blacklist contains domains, email addresses or IP addresses.

Having a domain blacklisted can prevent emails being sent. Instead, 'bounce back' messages are received from the server that has rejected the email.

Was this answer helpful? 0 Users Found This Useful (0 Votes)

Most Popular Articles

What's the difference between using mail.domain.com and imap/smtp.domain.com?

When selecting what credentials to use within your mail client, you have a choice between using...
What are my email sending limits?

The following limits apply to all messages sent via authenticated SMTP. This will primarily be...
What is IMAP?

IMAP stands for Internet Message Access Protocol and is a protocol used to access emails via an...
What is POP3?

POP3 stands for Post Office Protocol version 3 and refers to the protocol used to receive emails...
How do I add another server/include to an SPF record?

What's in this guide? Adding an SPF Include for: G Suite Office 365 Mailchimp SendGrid...