How to Set Up Microsoft 365 for Cold Email Sending

Microsoft 365 is the alternative to Google Workspace for cold email hosting. Some cold emailers prefer it for diversification or because their target prospects are primarily on Microsoft ecosystems. Step 1: Purchase Microsoft 365 Sign up for Microsoft 365 Business Basic ($6/user/month) at microsoft.com. Use your secondary cold email domain. Verify domain ownership by adding a TXT record to your DNS. Step 2: Create email accounts Add users through the Microsoft 365 Admin Center. Create two to three accounts per domain with professional, realistic names. Step 3: Configure DNS records Microsoft provides a comprehensive DNS setup guide during domain verification. You will need to add MX records, an autodiscover CNAME, and potentially other records depending on your configuration. Follow Microsoft's specific instructions for your domain registrar. Step 4: Set up SPF Add the Microsoft 365 SPF record to your DNS: v=spf1 include:spf.protection.outlook.com ~all. Verify with the SPF Checker. Step 5: Set up DKIM In the Microsoft 365 Defender portal, go to Email & Collaboration > Policies & Rules > Threat Policies > Email Authentication Settings > DKIM. Select your domain and enable DKIM signing. Microsoft will provide two CNAME records to add to your DNS. After adding them and propagation completes, enable DKIM signing. Step 6: Set up DMARC Add a DMARC TXT record: v=DMARC1; p=none; rua=mailto:dmarc-reports@yourdomain.com. Verify with the DMARC Checker. Step 7: Configure accounts Log into each account via Outlook on the web. Set up a simple text-only signature. Adjust settings as needed. Step 8: Connect to warmup and sending tools Microsoft 365 accounts connect to most cold email tools via OAuth or SMTP. Check your sending tool's documentation for Microsoft-specific setup instructions. Begin warmup immediately.

Microsoft-specific considerations

Microsoft 365 has stricter daily sending limits for new accounts (initially as low as 10,000 recipients per day for the entire tenant, with per-mailbox limits). Microsoft is also more aggressive about temporarily locking accounts that show unusual sending patterns. Ramp up very gradually on Microsoft 365.

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