How to manage Transactional Email blocklists

Reviewed on July 31, 2025

The Transactional Email (TEM) blocklist feature allows you to manage email addresses that generate errors, or bounces. Emails are automatically blocked when a mailbox does not exist, or is full, to prevent sending emails to a recipient address that is not reachable. You can also add emails to the blocklist manually if you subscribe to the TEM Scale plan and have a Scaleway domain.

Before you start

To complete the actions presented below, you must have:

• A Scaleway account logged into the console
• Owner status or IAM permissions allowing you to perform actions in the intended Organization. For blocklists your can apply the TransactionalEmailBlocklistFullAccess permission
• Configured your domain(s) with Transactional Email

How to add an email address to the blocklist

You can manually add addresses to your blocklist in the Scaleway console. Once added, the email remains blocked indefinitely until you [unblock it](# how-to-unblock-an-email-address) manually.

1. Click Transactional Emails in the Domains & Web Hosting section of the console side menu. Your domains display.
2. Click the domain for which you want to manage the blocklist.
3. Click the Blocklist tab.
4. Click + Add to blocklist. A pop-up appears.
5. Enter the recipient emails you wish to prevent from receiving emails from your domain.
   Important

   You can separate each email address by a comma to add multiple emails at once.

6. (Optional) Provide a reason for blocking the address.
7. Select a flag between:
   • Mailbox full - when the mailbox is full
   • Mailbox not found - when mailbox does not exist
8. Click Add to blocklist. The email is added to your blocklist.

How to monitor temporary blocklists

If any of your emails bounced, you will see a temporary blocklist entry containing the details of the email that bounced and the reason, or flag. Some examples of bounce reasons are:

• Mailbox full - when the mailbox is full
• Mailbox not found - when mailbox does not exist

The temporary blocklist entry is created automatically to prevent repeated attempts to send emails, which could damage your reputation.

To see the blocklist:

1. Click Transactional Emails in the Domains & Web Hosting section of the console side menu. Your domains display.
2. Click the domain whose blocklist you want to manage.
3. Click the Blocklist tab. Your blocklist displays, detailing the recipient email, the flags, the date the block began, and when it ends.

How to unblock an email address

You can unblock any address that was added to the blocklist. This is useful in cases where:

• A temporary error has been corrected. The recipient has freed up space in their mailbox, for example.
• An address becomes valid again after an update.

1. Click Transactional Emails in the Domains & Web Hosting section of the console side menu. Your domains display.

2. Click the domain whose blocklist you want to manage.

3. Click the Blocklist tab. Your blocklist displays.

4. Click Unblock next to the email address you wish to unblock. A warning pop-up appears.

   Important

   Make sure the issue causing the email's rejection is resolved before unblocking it to protect your reputation score and ensure optimal email deliverability.

5. Type UNBLOCK and click Unblock if you wish to continue. The email address is removed from your blocklist.