Seeing a mailbox flagged as "burned," a domain on a blacklist, or a scary spam score can be alarming — but the same word can mean very different things. There are three separate situations here, and each has its own answer. The first step is always to work out which one you're actually looking at.
Situation 1: Smartlead or Instantly shows a "burned" status
Tools like Smartlead and Instantly run their own shared warmup pools, and a "burned" label usually reflects the rotating IPs inside that tool's pool — not the reputation of your Maildoso domains or mailboxes.
If your mailboxes are active and configured correctly on Maildoso, a "burned" flag in the sequencer is not a sign that your domains have a real reputation problem.
What to do: keep warmup running normally. Don't pause campaigns, don't reduce volume, and don't replace domains based on this label alone.
Tip: check the reputation the dashboard reports for that mailbox instead — see Understanding your mailbox reputation scores (Google Score & Microsoft Score).
Situation 2: A blacklist checker (e.g. SURBL) flags your domains or IPs
We send from a rotating pool of IPs, so from time to time one of those IPs may appear on a blacklist such as SURBL. This does not mean your domain's reputation is damaged.
In 2026, a SURBL listing has no measurable impact on inbox placement — major providers like Gmail and Outlook do not use SURBL as a primary filtering signal.
What matters is that your SPF, DKIM, and DMARC are passing, which they are on our managed setup.
What to do: keep sending and warming up as usual. There's nothing to fix and no need to replace domains.
More detail: My domains are listed on SURBL / a blacklist — what should I do?, SURBL Listings and Deliverability Impact, and One of my sending IPs shows as blacklisted.
Situation 3: Google actually rejects your emails, or a placement test shows 0% inbox
This one is different. A genuine rejection message from Google, or a placement test that consistently shows almost no inbox placement, is not just an external checker being noisy — it points to a real issue that should be looked at properly.
What to do: don't ignore it, and don't assume it's a false positive. Contact us so our deliverability specialists can review your specific case.
To speed up the review, send us the full headers of one rejected email, or a screenshot of the placement test, along with your account email and the affected domains or mailboxes.
A common question: "A checker says my DKIM is missing"
This is normal and expected. Because we use custom DNS records for our own sending infrastructure, some external tools report our DKIM as "missing" even though it's correctly in place — this is by design and follows Google's guidelines. We don't add a custom DKIM on top of our infrastructure. You can confirm everything is in place with a standard lookup tool such as easydmarc.com. See My DKIM or DMARC isn't detected by a third-party checker. If you're seeing actual rejected emails from Google, that's Situation 3 above — contact us.
Your dashboard's own reputation view
Your dashboard already gives you a reliable read on mailbox health, so you don't have to rely on a sequencer's "burned" label. On the Email accounts page, and in each mailbox's Deliverability panel, you'll see a Google Score and a Microsoft Score with the date they were last checked. A brand-new mailbox can read low during its first couple of weeks of warmup — that's expected, so let it finish warming up before reading anything into the score. Full explanation: Understanding your mailbox reputation scores (Google Score & Microsoft Score).
It also helps to know how mailbox rotation is designed to work: individual "burned" mailboxes are meant to take the hit instead of your main domain. If a mailbox does get burned, the recovery is simple — stop sending prospecting emails from it, but keep warming it up. In about 2–4 weeks it recovers. Replacing domains is rarely necessary.
The key takeaway
"Burned," a blacklist flag, and a real rejection look similar but are three different things. A label inside a sequencer or a blacklist checker almost always reflects rotating IPs rather than your domain, and warmup should simply continue. A genuine Google rejection or a 0% placement test is the case where you should reach out so we can dig into it. When in doubt, contact us with the details above and we'll help you tell them apart.