What is Email Greylisting?

What is Email Greylisting?

Email greylisting is a method through which email users are protected from spam. A mail transfer agent also abbreviated as MTA rejects the email with a temporary rejected error. If the SMTP is legitimate then it makes several attempts to get the emails delivered until they are finally accepted. A server that works on mass email spam does not use such technologies at all.  

Contents of the Article

  1. How does greylisting work?
  2. How to avoid greylisting?

How Email Greylisting Works?

As per the SMTP rules, a greylisting server makes sure that an email from unknown servers is blocked and a “temporary rejection” error is given to the sending server. If the SMTP server is legitimate then it will try for the coming 15 minutes on and on until the message is delivered. 

For the first time if the email server has let the email pass then there subsequently there is no delay at all. The greylisting server will remember the details of the sender and will never delay such emails at all. 

The temporary error messages in this regard are also cost-efficient and do not require much CPU and processing power. It makes sure that fewer resources are used and the message is rejected unlike other spam programs on the market. 

If the SMTP is not set up properly then the delay can be more than that 15 minutes which can cause massive delays especially if the recipient wants instant emails or the message is important. The spam servers can also adjust to the greylisting and send the messages by reattempting. It also means that this method gets weakened. The servers during the delay get time to identify the spam emails and plan further courses of action.


How to Avoid Email Greylisting?

  • Take care of your IP-address reputation
  • Use a reliable domain
  • Sign your email with a real sender’s name
  • Allow instant unsubscribing
  • Format the headings and the message correctly
  • Avoid using stop-words
  • Take care of IP address Reputation

DooxMail ensures that your IP reputation is maintained and for this, all measures are taken. It will also get you whitelisted by the greylisting servers. 

  • Use a Reliable Domain

Make sure that the domain you are using is highly reputed. It comes after the @ sign in your email address. Though it takes some time once the reputation is established you get no issue of greylisting.

  • Sign Your Email with Real Sender Name

It makes sure that your open rate increases so that your audience also gets in touch with you and this will increase engagement in your emails. The sender’s name also alerts the spam filters not to block the emails. It also increases your domain reputation at the same time.

  • Allow Instant Unsubscribing

This is another important that makes your messages more authentic and increases the chances of not getting spammed. If this choice is not given then the only way out they have is to mark the email as spam which will ensure your messages are never delivered to the inbox of this particular recipient. 

  • Format the headings and messages correctly

Format your messages and emails according to HTML standards and RFC 5322 so that they are never delayed and spammed.

  • Avoid using Stop words

The words like amazing, buy, free, etc. can alert the greylisting and can lead to an undelivered message, Make sure that such words are never used.