Open Relay
Also known as: Insecure relay
An open relay is an email server configured to allow anyone on the internet to send email through it, regardless of who they are.
An open relay is a misconfigured mail server that accepts and forwards email from unauthenticated senders to third-party destinations. In the early days of the internet, this was common. Today, it is a massive security risk.
Spammers aggressively scan for open relays to hijack them for sending millions of spam emails. If your server is identified as an open relay, it will be blacklisted almost immediately by every major blocklist (like Spamhaus), causing all your legitimate mail to bounce.
Securing a mail server involves ensuring it only relays mail for authorized users or specific IP addresses.
Related Terms
Abandoned Cart Email(Cart Abandonment Email)
An automated email that goes out when someone adds items to their cart but leaves without buying. These emails show what they left behind and usually include a direct link back to their cart. Most businesses send a series of 2-3 reminders over a few days, sometimes sweetening the deal with a discount or free shipping offer.
Learn more →Email Geek
An email geek is someone who loves the craft of email and works to make every send better. They test ideas, care about deliverability, and treat subscribers like real people, not just numbers on a list.
Learn more →Email Sequence(Email Series)
An email sequence is a planned set of emails that send automatically after someone takes a specific action, like signing up or buying. It helps you guide subscribers through a simple journey without sending every email by hand.
Learn more →Batch Email(Batch Send)
Batch email is when you send the same email to many people at once. Your email platform sends it in groups so you can reach a large list without hurting deliverability.
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