Cold email is a deliverability game. The mailbox you send from has a reputation with every receiving mailbox provider, and that reputation is built on two things: how the domain is configured, and how the mailbox has behaved over the last few weeks. BrandJet AI handles the behavior part with warmup, but you have to get the domain configured correctly first.
This article covers adding a domain, the DNS records you need, what the status indicators mean, and how warmup actually works.
Why this matters
If you send cold email from your real company domain, even one or two complaints can drag your reputation down for months. That hits every email your team sends, not just cold outreach. The safer pattern is to use a separate domain (or a few separate domains) for cold sending, keep your main domain for transactional and one to one mail, and use BrandJet AI to warm the cold domain up before you start campaigns.
If you do not want a separate domain and you are sending warm follow ups rather than cold outreach, you can still connect your real mailbox. Just expect tighter sending limits and keep volumes very low.
Add a domain you already own
If you already own a domain, you can add it without changing nameservers.
From the sidebar, click Domains, then click Add domain.
Type in the domain you want to use (for example acme.com or acme.io).
BrandJet AI generates the DNS records you need to add at your current DNS host. These are SPF, DKIM, DMARC, and an MX record.
Copy each record into your DNS provider (GoDaddy, Cloudflare, Namecheap, Route 53, or whichever you use). Save changes.
Come back to BrandJet AI and click Verify. The check runs in a few seconds.
You do not need to change your nameservers. Adding the records alongside whatever you already have is enough. The MX record is the one that affects inbound mail flow, so make sure you understand the implications before you add it to a domain that already receives mail.
Buy a new domain through BrandJet AI
If you do not have a domain yet, you can buy one inside the app.
From the sidebar, click Domains, then click Buy domain.
Search for the name you want. BrandJet AI suggests similar TLDs (.io, .ai, .com, .co) and shows which are available.
Pick a domain and pay for it. Registration is annual.
The domain auto configures in BrandJet AI. The DNS records are added for you, the mailboxes are created, and the domain is ready to add to a campaign.
This is the easiest path if you want to set up cold infrastructure without learning DNS. Most teams buy two to four domains per campaign and rotate sending across them.
Understand the status indicators
After you add a domain, you will see two states on the domain card.
Propagated. The DNS records you added have spread across the internet and BrandJet AI can read them. DNS changes can take a few minutes or a few hours to propagate depending on your DNS host. Cloudflare and Namecheap are usually fast. GoDaddy can take up to a day. If a domain is stuck at Not propagated after twelve hours, the most common cause is that the records were added with a typo or the wrong record type. Open the domain and compare each record to what BrandJet AI shows.
Active. The domain is configured correctly and ready to send. Active means all four DNS records (SPF, DKIM, DMARC, MX) are present and pointing the right way.
A domain can show as Not propagated and Active at the same time when records were partially added. That is fine. The card is telling you the active records are working. Add the missing ones to make it fully propagated.
How email warmup works
Warmup is the process of building a sending reputation for a brand new mailbox. BrandJet AI sends low volume mail to a network of other warmup mailboxes, those mailboxes mark the messages as important, reply to some of them, and move them out of spam if they land there. Over a few weeks, that pattern teaches receiving providers (Gmail, Outlook, Yahoo, and the rest) that your mailbox is sending wanted mail.
To turn warmup on:
From the sidebar, click Email accounts.
Click the mailbox you want to warm up.
Open the Warmup tab.
Set the ramp up curve. The default ramps from one warmup mail per day to about forty per day over four weeks. Most teams use the default.
Turn the toggle on.
Warmup runs every day, including weekends, and you do not need to do anything else. The mailbox stays usable for campaigns while warmup runs, but for the first two weeks we recommend keeping campaign sends very low and letting warmup do most of the work.
When is warmup complete
Warmup never really stops, because reputation is something you maintain, not something you finish. But there are three signals that tell you the mailbox is ready to handle real campaign volume:
The warmup chart in the Warmup tab shows the daily volume holding steady at the target you set (usually forty per day).
The spam rate shown on the same chart is under five percent.
The mailbox has been warming for at least fourteen days.
When all three are true, you can start ramping campaign sends. We recommend going up by twenty percent per week rather than jumping straight to the maximum. Even a perfectly warmed mailbox can get throttled if it suddenly starts sending three times what it sent yesterday.
You can keep warmup running indefinitely while campaigns are active. The two do not conflict, and keeping warmup on is a good way to maintain reputation when campaigns are paused.
Common warmup errors
Authentication failed. The warmup process tried to log in to your mailbox and the provider refused. Reconnect the email account from Accounts. This is usually caused by a password change, a security challenge, or MFA being turned on.
MX records error. The MX record on the domain is missing or pointing somewhere else. Open Domains, find the affected domain, and check the MX record. If you deleted it while reorganizing DNS, add it back.
Warmup paused. You hit the manual pause toggle. Turn it back on.
Warmup running but no volume. The mailbox is in the early days of the ramp curve, where it sends one or two messages a day. Wait at least seventy two hours before troubleshooting. If volume still has not picked up, open a support ticket.
What to do next
Once your domain is active and at least one mailbox has been warming for fourteen days, you are ready to load real leads. Move to Upload or find your leads, then Create a multichannel campaign.