After adding a custom domain, add the DKIM, SPF, DMARC, and MX records
Sentvia returned in Namecheap.
Open Advanced DNS
Namecheap → Domain List → Manage next to your domain → Advanced DNS tab.
Enter the Host without your domain
Like GoDaddy, Namecheap appends your domain automatically. In the Host field enter only the
part before your domain — e.g. token._domainkey.mail (not …mail.yourco.com). Use @ for the
root.
Add DKIM (CNAME ×3) + SPF/DMARC (TXT)
Add New Record → choose CNAME Record or TXT Record, set Host and Value exactly as
shown. Leave TTL on Automatic.
Add the MX records
Add MX Record entries; Namecheap has a separate Priority field — set it to 10. (If
“Email” is set to Namecheap’s own service, switch the Mail Settings dropdown to Custom MX
first.)
In Host, enter only the part before your domain — Namecheap appends the rest. And make sure
Mail Settings is set to Custom MX, or your MX records won’t apply.
POST /domains/{id}/verify to re-check. 
