The latest articles on DEV Community by node mail (@nodemail). https://dev.to/nodemail https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F3903361%2F3696b5e9-4500-4330-a5c8-87adbd4df429.png https://dev.to/nodemail en node mail Wed, 29 Apr 2026 01:57:23 +0000 https://dev.to/nodemail/how-i-built-a-temp-email-service-with-real-hotmail-accounts-using-flask-microsoft-graph-api-4m4d https://dev.to/nodemail/how-i-built-a-temp-email-service-with-real-hotmail-accounts-using-flask-microsoft-graph-api-4m4d <h2> The Problem </h2> <p>If you've ever tried to use a disposable email service on Instagram, <br> TikTok, or Netflix — you know the pain. They get rejected instantly <br> because platforms maintain blacklists of known fake domains.</p> <p>I kept hitting this wall while testing registration flows for my <br> own projects. So I built the solution myself.</p> <h2> The Idea </h2> <p>Instead of fake domains, use <strong>real, active Microsoft accounts</strong> <br> as a temporary inbox pool. Assign them to users on demand, let <br> them receive the verification code, then reclaim the address.</p> <p>Simple concept. Surprisingly tricky to execute at scale.</p> <h2> Tech Stack </h2> <ul> <li> <strong>Backend:</strong> Python / Flask</li> <li> <strong>Database:</strong> MySQL (PyMySQL)</li> <li> <strong>Email access:</strong> Microsoft Graph API (OAuth2 + refresh tokens)</li> <li> <strong>Auth:</strong> bcrypt + session-based for web, API key for REST</li> <li> <strong>Payments:</strong> NowPayments (crypto)</li> <li> <strong>Rate limiting:</strong> flask-limiter</li> </ul> <h2> The Hard Part — Microsoft Graph API </h2> <p>Getting inbox access via Graph API is straightforward for a single <br> account. The challenge is doing it for hundreds of accounts without:</p> <ul> <li>Hitting rate limits</li> <li>Token expiry causing missed emails</li> <li>Accounts getting flagged for unusual activity</li> </ul> <p>My solution: a warmup step on every new assignment that makes a <br> lightweight Graph API call to "activate" the session before the <br> user sends their verification request. This reduced missed emails <br> significantly.</p> <p>The API<br> Every account gets an API key. Developers can automate the whole flow:</p> <p>Business Model<br> Pay-as-you-go credits. No subscription. Refund if no email arrives.</p> <p>This model works well here because users don't need temp emails every day — a subscription would feel like a tax on infrequent use.</p> <p>What I Learned<br> The moat isn't the code — it's the operational side (maintaining a healthy account pool)<br> API-first opens a second market: developers who need this at scale pay more per unit than casual users<br> Refund policy removes the biggest objection ("what if it doesn't work?")<br> Try It<br> 🔗 nodemail.store<br> 📄 API Docs</p> <p>Happy to answer questions about the Graph API integration, the account pool management, or anything else in the comments.</p> python webdev api showdev