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Verifying an Email Sending Domain

To send email from you@yourcompany.com, you must prove ownership of yourcompany.com by publishing DNS records. Manage domains at Email → Domains. Add a new one at Email → Domains → New.

Add a domain

  1. Open Email → Domains → New.
  2. Enter the apex domain (e.g., yourcompany.com, not mail.yourcompany.com). Sending from subdomains is supported once the apex is verified.
  3. Choose a region (US East default; EU available for residency).
  4. Click Add.

The domain detail page (/email/domains/<id>) opens with the records you need to publish.

DNS records you'll publish

Record Purpose Required?
DKIM (3 CNAMEs) Cryptographically sign each message so receivers can verify it's from you Required
SPF (TXT) Authorize Blocx's sending IPs to send for your domain Required
MAIL FROM (MX + TXT) A send.<yourdomain> subdomain we use as the bounce return path; aligns SPF with the visible From Required
DMARC (TXT) Tell receivers what to do with mail that fails authentication; enables reporting Strongly recommended
BIMI (TXT, optional) Display your logo next to mail in supporting clients Optional, requires a VMC

Copy the records into your DNS provider exactly as shown on the detail page. Do not edit values or wrap them in quotes that aren't shown.

SPF gotcha

If you already have an SPF record (v=spf1 ...), merge rather than duplicate. Multiple v=spf1 TXT records is itself an SPF failure. The detail page shows a merged value you can paste, or include our include: mechanism in your existing record:

v=spf1 include:spf.otterblocx.com include:_spf.google.com -all

Verification

Blocx checks DNS automatically on a regular schedule, and you can also click Re-check now on the domain detail page to force a lookup. When all Required records resolve correctly the domain flips to Verified and you can immediately send from any address on it. Organization owners and admins are emailed when a domain finishes verifying.

Most domains verify within 5–30 minutes. Slow DNS providers (or aggressive caching) can take up to 48 hours.

Status meanings

Status Meaning Next step
Pending At least one record not yet detected Wait, or re-check DNS with dig
Verified All required records present Start sending
Partially verified DKIM ok but SPF or MAIL FROM missing Add the remaining records — partial verification means deliverability suffers
Failed A previously-verified record changed or was removed Click the domain to see which

Sending after verification

curl -X POST https://api.otterblocx.com/email/send \
  -H "x-access-key-id: $BLOCX_ACCESS_KEY_ID" \
  -H "x-secret-access-key: $BLOCX_SECRET_ACCESS_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "hello@yourcompany.com",
    "to":   "user@example.com",
    "subject": "Welcome",
    "html": "<p>Welcome aboard.</p>"
  }'

Or with the SDK:

import { createBlocxClient, Email } from '@otterlabs/blocx'

const { client } = createBlocxClient({
  accessKeyId:     process.env.BLOCX_ACCESS_KEY_ID!,
  secretAccessKey: process.env.BLOCX_SECRET_ACCESS_KEY!,
})

await Email.sendEmail({
  client,
  body: {
    from: 'hello@yourcompany.com',
    to:   'user@example.com',
    subject: 'Welcome',
    html: '<p>Welcome aboard.</p>',
  },
})

Tips for deliverability

Troubleshooting

Use the Re-check now button on the domain detail page to force an immediate DNS lookup. If records still don't resolve:

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