A Global Custom Domain Tracking (GCDT) domain is a single tracking domain set up once for your whole Maildoso account. Instead of configuring a custom tracking domain per mailbox or per campaign in your sending tool, we apply tracking consistently across all your emails from our side.
It's already on — nothing to configure
As the setting itself says in your dashboard: "We handle all custom domain tracking on our side using global domain preferences. No need to configure anything in your cold outreach tool. This significantly improves deliverability." It's enabled by default on your account, so you don't need to set up a custom tracking domain in your sending tool.
Where to find it
Click your account email / profile icon in the top-right corner and open Settings.
On the General tab you'll see the Global Custom Domain Tracking toggle at the top. Leave it on for the best deliverability.
Why you can't add your tool's own tracking domain
Because we fully manage your domain's DNS, we don't support adding a third-party / custom tracking CNAME from your sending tool (Instantly, Smartlead, lemlist, etc.). Sending still works normally — only the tool's own custom open/click tracking domain can't be verified on a Maildoso-managed domain. GCDT already covers link tracking for you. For the fuller picture of what managed DNS means, see How DNS works on your Maildoso domains (managed DNS).
Good to know
This feature is currently available for SMTP mailboxes only. (Google Workspace mailboxes are also not currently available for new purchase — see our Google Workspace availability article.)
If a recipient's email client shows a security or "suspicious link" warning on links in your emails, it's usually the tracking redirect rather than your actual destination link — mail clients sometimes flag unfamiliar redirect domains this way. If you're seeing this, contact support with an example message and the flagged link so we can look into the tracking domain for your account; in the meantime you can turn the GCDT toggle off in Settings → General to send links unwrapped while we investigate.