What is an email suppression and how do I remove one?

When Plain can't deliver an email to an address, the address can end up on a suppression list. While an address is suppressed, emails to it are not sent. This article explains how that happens and how to remove a suppression.

How suppressions happen

Plain sends email through an email delivery provider, which keeps a suppression list. An address is added to it for one of three reasons:

• Hard bounce: the recipient's mail server permanently rejected an email, for example because the mailbox doesn't exist. The address is suppressed automatically so that Plain stops sending to it.

• Spam complaint: the recipient marked an email as spam. The address is suppressed automatically.

• Manual suppression: the address was added to the suppression list directly rather than through a failed delivery.

How to tell an address is suppressed

When you reply to a thread and the recipient is suppressed, the email isn't sent. A notice appears on the thread Timeline saying the address is on a suppression list because a previous send to it failed. If every recipient on the email is suppressed, nothing is sent.

How to remove a suppression

You can check an address and reactivate it from your workspace settings:

1. Go to Settings and open Emails.

2. Scroll to Email suppressions.

3. Enter the exact email address, for example customer@example.com, and select Check.

4. Plain shows whether the address is suppressed, the reason (hard bounce, spam complaint or manual suppression) and the date it was suppressed.

5. Select Reactivate email address and confirm.

Once reactivated, Plain can send to the address again straight away. Reactivating does not resend emails that failed earlier, so send a new reply to the customer.

Who can remove a suppression

By default, team members with the Owner, Admin, Support or Viewer role can check whether an address is suppressed. Only Owners and Admins can reactivate one. If the Reactivate email address button is disabled, ask an Owner or Admin to do it.

Suppressions that can't be removed

Suppressions caused by a spam complaint can't be removed in Plain. The Reactivate button isn't shown for these addresses. If the customer wants to receive emails from you again, contact Plain support.

Before you reactivate

• Check the address is correct. If the customer has a typo in their email address, update it on the Customer instead.

• Only reactivate if the recipient expects to hear from you. If the address is still invalid, the next email may bounce again.