Mailgun API returns 200 success response but emails not delivered in Angular/TypeScript app

[Stella_Dreamer]

I’m working on an Angular mobile application and trying to send emails through Mailgun’s REST API. The email sending function gets triggered when users complete a specific workflow in my app.

const emailData = {
  from: '[email protected]',
  to: userEmail,
  subject: 'Action Completed',
  text: 'Your request has been processed successfully'
};

this.http.post('https://api.mailgun.net/v3/mydomain.com/messages', emailData)
  .subscribe(response => {
    console.log('API Response:', response);
  });

The weird thing is that I’m getting what looks like a successful response from the API. The status shows 200 and everything appears to work correctly. But the actual emails never reach the intended recipients. I’ve checked spam folders and everything but nothing shows up.

During development I had to deal with CORS issues by using a browser extension, but the API calls seem to go through fine now. Has anyone experienced similar issues where Mailgun reports success but doesn’t actually deliver the messages?

[Tom_Artist]

Been dealing with Mailgun for two years across different projects. This sounds like a domain config issue I’ve seen tons of times. Getting 200s but no emails? Check if your sending domain is actually verified in Mailgun’s control panel. The API accepts requests from unverified domains and returns success, but drops the messages silently.

Also check your DNS records - SPF, DKIM, and MX need to match Mailgun’s specs exactly. I’ve seen partial DNS setups cause this exact problem. Hit up the logs section in your Mailgun dashboard to see what’s really happening to those messages.

[DancingButterfly]

Had this exact issue 6 months ago with my Angular project. That 200 response just means your request hit Mailgun’s servers - doesn’t mean the email actually sent. You’re probably missing proper auth. Make sure you’re using basic auth with your API key. Check your domain verification in the Mailgun dashboard too. Unverified domains fail silently even when the API says everything’s fine. Also double-check you’re hitting the right endpoint. EU accounts need api.eu.mailgun.net, not the standard api.mailgun.net.

[aroberts]

for sure! make sure you include the right auth header. mailgun won’t send if the api key ain’t there, even if you see a 200. try adding Authorization: Basic ${btoa('api:YOUR_API_KEY')} in your headers and check if that helps.

[SpinningGalaxy]

Check if you’re in Mailgun sandbox mode! Had the exact same issue - turns out sandbox only sends to authorized recipients. Go to your dashboard settings and make sure your account’s actually activated. Also double-check your ‘to’ email format is right - Mailgun’s super picky about formatting.

[alexlee]

You’re missing auth headers completely. Mailgun needs basic authentication with your API key, but your HTTP request has none. Without proper auth, Mailgun accepts the request but won’t process it - that’s why you get a 200 response with no delivery.

I hit this same issue rebuilding a customer onboarding flow last year. Add the Authorization header with your API key encoded properly. Also, sending emails directly from Angular exposes your API credentials to anyone checking the network tab. Proxy through your backend instead.

Check your Mailgun dashboard logs - they’ll show auth failures even when the API returns success codes.

[byteBard_007]

The Problem:

You’re receiving a 200 OK response from the Mailgun API when sending emails from your Angular application, yet the emails aren’t reaching their recipients. This suggests a problem with your email sending process, despite the seemingly successful API call. You suspect the issue may relate to authentication or domain configuration, especially considering previous CORS problems during development. The current implementation uses this.http.post to send the email data directly from the frontend.

Understanding the “Why” (The Root Cause):

The core issue is a flawed approach to sending emails directly from your Angular frontend. This method exposes your Mailgun API keys directly to the client-side, posing a significant security risk. Furthermore, relying solely on the 200 OK response from the API is insufficient. A successful API call merely indicates that the request reached Mailgun’s servers; it doesn’t guarantee successful email delivery. Mailgun may silently drop messages due to missing authentication, incorrect domain configuration, or other factors, without explicitly reporting failure in the API response. Directly sending from the frontend also introduces unnecessary complexities with CORS handling.

Step-by-Step Guide:

1. Migrate Email Sending to Your Backend: The most crucial and secure step is to move the email sending logic to your backend server. This protects your API keys and simplifies debugging. You can use any backend technology you prefer (Node.js, Python, etc.). Your Angular application will then make a request to your backend API endpoint to trigger email sending. This isolates the sensitive API keys from the client side.

2. Implement Secure Authentication: Within your backend email sending function, ensure proper authentication with your Mailgun API key using the recommended Authorization header with Base64 encoding:

const apiKey = 'YOUR_MAILGUN_API_KEY'; //Store this securely in environment variables!
const auth = Buffer.from(`api:${apiKey}`).toString('base64');

const options = {
  method: 'POST',
  url: 'https://api.mailgun.net/v3/YOUR_DOMAIN/messages',
  headers: {
    'Authorization': `Basic ${auth}`,
    'Content-Type': 'application/x-www-form-urlencoded' //Note: this might differ based on your Mailgun setup.
  },
  form: {
    from: '[email protected]',
    to: userEmail,
    subject: 'Action Completed',
    text: 'Your request has been processed successfully'
  }
};

3. Verify Mailgun Domain Verification and DNS Records: In the Mailgun control panel, ensure that your sending domain (mydomain.com in this example) is fully verified and that all required DNS records (SPF, DKIM, and MX) are correctly configured and propagated. Incorrect DNS settings are a frequent cause of email delivery failures. Allow sufficient time (several hours) for DNS propagation.

4. Check Mailgun Logs: Carefully examine the Mailgun logs for any error messages or bounce reports. This will provide valuable insights into why emails are not being delivered. Look for issues like authentication failures or domain configuration problems.

5. Test Thoroughly: After implementing these changes, conduct thorough testing by sending test emails to various recipients (including different email providers). Use a service like mail-tester.com to assess your email authentication and deliverability scores.

Common Pitfalls & What to Check Next:

• Incorrect API Endpoint: Double-check that you are using the correct Mailgun API endpoint. If you’re using a European region account, make sure to use api.eu.mailgun.net.
• Sandbox Mode: If you’re still in Mailgun’s sandbox mode, emails will only be delivered to authorized recipients. Check your Mailgun settings to verify your account is activated.
• Email Formatting: Ensure your to email addresses are correctly formatted. Mailgun is sensitive about email address formatting.
• Rate Limiting: Mailgun may apply rate limits to prevent abuse. If you’re sending a large volume of emails, consider implementing strategies to gradually increase your sending rate (“warming up” your domain).

Still running into issues? Share your (sanitized) config files, the exact command you ran, and any other relevant details. The community is here to help!