Understanding DKIM and How to Set It Up for Google Workspace and Microsoft 365

What is DKIM?

DKIM, or DomainKeys Identified Mail, is an email authentication method designed to detect forged sender addresses in emails. It works by adding a digital signature to each outgoing email, which can be verified by the recipient’s email server to ensure that the email has not been altered and truly comes from the domain it claims to be from.

Why is DKIM Important?

Implementing DKIM helps:

• Protect your domain from being used in email spoofing or phishing attacks.
• Ensure that your emails reach their recipients without being marked as spam.
• Enhance the trust and credibility of your email communications.

How to Set Up DKIM for Google Workspace

Step 1: Generate the DKIM Keys

1. Log in to your Google Admin console at admin.google.com.
2. Go to Apps > Google Workspace > Gmail > Authenticate Email.
3. Select the domain you want to authenticate.
4. Click on Generate New Record.
5. Choose a DKIM key bit length (2048-bit is recommended for better security).
6. Click Generate.

Step 2: Add the DKIM Key to Your DNS

1. After generating the key, you will get a DNS TXT record.
2. Log in to your domain provider’s DNS management page.
3. Add a new TXT record:
   • Host/Name: The name provided in the Google Admin console (e.g., google._domainkey).
   • TXT Value: The long string of characters provided in the Google Admin console.
4. Save the DNS record.

Step 3: Start Authenticating Emails

1. Go back to the Google Admin console.
2. Click on Start Authentication.

Your domain’s outgoing emails will now be signed with DKIM, ensuring they are protected from tampering.

How to Set Up DKIM for Microsoft 365

Step 1: Enable DKIM Signing for Your Custom Domain

1. Log in to the Microsoft 365 admin center at admin.microsoft.com.
2. Go to Exchange admin center > protection > dkim.
3. Select your domain and click Enable.

Step 2: Add the CNAME Records to Your DNS

1. You will see instructions to add two CNAME records to your DNS.
2. Log in to your domain provider’s DNS management page.
3. Add the following CNAME records:
   • Record 1:
     • Host/Name: selector1._domainkey
     • Value: The provided address in Microsoft 365 (e.g., selector1-yourdomain-com._domainkey.yourdomain.onmicrosoft.com).
   • Record 2:
     • Host/Name: selector2._domainkey
     • Value: The provided address in Microsoft 365 (e.g., selector2-yourdomain-com._domainkey.yourdomain.onmicrosoft.com).
4. Save the DNS records.

Step 3: Activate DKIM Signing

1. Go back to the Exchange admin center.
2. Refresh the page and click Enable next to both selectors.

Your domain’s outgoing emails will now be signed with DKIM, ensuring they are protected from tampering.

Need Help?

If setting up DKIM is outside your comfort level, don’t worry. At BBComputing, we specialize in helping businesses implement these security measures to protect their email communications. Contact us today, and we’ll ensure your emails are authenticated and secure.

By following these steps, you can enhance the security of your email communications. DKIM helps prevent your domain from being used in malicious activities, protecting both your reputation and your recipients.

Feel free to reach out to BBComputing if you need any assistance with this process!