Validation results and blacklist reasons
Every result comes with the check that decided it, so you know what to do.
Email validation
Each address is valid, risky or invalid.
| Result | Reason | What it means |
|---|---|---|
| Invalid | Bad syntax | The address is not written correctly. |
| Invalid | No mail server | The domain has no records that accept mail. |
| Invalid | Mailbox not found | The receiving server said the mailbox does not exist. |
| Risky | Disposable domain | A throwaway address service. |
| Risky | Role address | A shared mailbox such as info@ or support@. |
| Risky | Accepts everything | The server accepts any address, so we can't confirm this one. |
| Risky | No clear answer | The server timed out or deferred. Try again later. |
| Valid | Mailbox accepted | The server confirmed the address. |
Mailbox-level checks depend on your plan. Where they are not included, checks stop at the domain level.
Blacklist severity
- Critical. Widely used by mailbox providers. A listing here usually affects delivery. Act first.
- Important. Used by some providers. Worth fixing soon.
- Informational. Small or niche lists. Note it, don't panic.
A list that did not answer is shown as an error, never as clean.
After a listing
- Find out why. A new IP may carry the previous owner's history. A server may have been compromised or misconfigured.
- Fix the cause before asking for removal. Most lists re-list quickly if the cause remains.
- Use the removal link shown with the result.