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Custom Domain SMTP Configuration

This documentation guides you through setting up SMTP for a Custom Domain in Orkap. Follow these steps to authenticate your domain, configure DNS, create credentials, and connect your SMTP successfully.


Requirements to Setup Custom Domain SMTP

  • Domain with DNS access
  • SMTP server (self-hosted or third-party)
  • Proper SMTP credentials

Configure DNS Records

Correct DNS configuration ensures maximum deliverability.

SPF (Sender Policy Framework)

Add a TXT record:

Name:   @
Type: TXT
Value: v=spf1 include:your-smtp-service.com -all

DKIM (DomainKeys Identified Mail)

Generate a DKIM key pair in your SMTP service or on your server. Add a TXT record:

Name:   selector._domainkey
Type: TXT
Value: v=DKIM1; k=rsa; p=PUBLIC_KEY

DMARC (Domain-based Message Authentication, Reporting & Conformance)

Add a TXT record:

Name:   _dmarc
Type: TXT
Value: v=DMARC1; p=none; rua=mailto:[email protected]; ruf=mailto:[email protected]; pct=100

Obtain SMTP Credentials

Depending on your setup, you may need to create or retrieve SMTP credentials.

Self-Hosted SMTP

  • Create a mail user or service account on your SMTP server.
  • Record the username and password you assign.

Third-Party SMTP Service

  • Log into the service dashboard.
  • Navigate to SMTP credentials or API keys.
  • Generate and copy your credentials.

SMTP Server Configuration Details

Use the following settings in your mail client or application:

FieldValue
SMTP Hostsmtp.yourdomain.com
SMTP Ports25 (unencrypted), 587 (STARTTLS), 465 (SSL/TLS)
EncryptionSTARTTLS (port 587) or SSL/TLS (port 465)
AuthenticationRequired
Username[email protected]
Passwordyour-smtp-password or API key

Verify Connectivity

Ensure that your server or local machine can reach the SMTP endpoint.

Telnet (unencrypted or to start TLS later)

telnet smtp.yourdomain.com 587
OpenSSL s_client (tests STARTTLS handshake)

openssl s_client -starttls smtp -connect smtp.yourdomain.com:587

You should see a 220 greeting and be able to issue SMTP commands like EHLO.

Test Email Delivery

After adding a mailbox in the Orkap dashboard, ensure the following steps are completed before sending any outreach email:

  • Send a test message from your client or application
  • Check SMTP server logs or your service dashboard for delivery activity
  • Confirm the message arrives in your recipient’s inbox or spam folder