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Why Subscribers Get Blacklisted

In Onyx, the Blacklist is a safety mechanism designed to protect your sender reputation. When a subscriber is moved to the blacklist, Onyx will automatically stop all outgoing mail to that address. This prevents you from being flagged as a spammer by global inbox providers.

Primary Reasons for Blacklisting

1. Hard Bounces (Permanent Failure)

A Hard Bounce occurs when an email is permanently rejected because the email address doesn’t exist or the domain is invalid.

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Hard Bounce Alert: Onyx blacklists any email that returns a Hard Bounce immediately. Continuing to send to non-existent addresses is the #1 signal to Gmail that you are using an unverified or “scraped” list.

2. Spam Complaints (The “Report” Button)

When a user clicks “Report Spam” in their inbox, the provider sends a feedback loop to Onyx. To protect your domain from being totally blocked by Google or Outlook, we immediately blacklist that user so you never “annoy” them again.

3. Inactive or Full Mailboxes

If a mailbox is over quota (full) or has been inactive for a long period, providers will eventually stop accepting mail. If Onyx receives multiple “Soft Bounces” for the same reason over several days, the system will escalate that contact to the Blacklist to save your deliverability score.

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Pro Tip: Regularly use a list cleaning service (like NeverBounce or ZeroBounce) before importing old leads into Onyx. This prevents “Blacklist spikes” during your first few broadcasts.

4. Manual Blacklisting

You can also manually blacklist domains or specific competitors. If you see a suspicious number of signups from @disposable-mail.com or similar temporary services, you can block them globally in your settings.

Can I Remove Someone from the Blacklist?

While you can manually remove a contact from the blacklist in Onyx, you should only do so if you have proof that the email address is now valid (e.g., the user contacted you directly).

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Warning: Forcing an email out of the blacklist and sending to it again after a “Spam Complaint” is a violation of anti-spam laws and will lead to your IP being permanently blocked.