没有不值得去解决的问题,也没有不值得去学习的技术!

Fixing Gmail Delivery Issues After Switching From Zoho Mail to QQ Enterprise Mail: A Failed Email Selection Postmortem (SPF + DKIM in Practice)

图12:Gmail 收件箱成功收到邮件

🧭 1. Starting Point: Attempting to Set Up a Business Email with Zoho Mail

Initially, I wanted to set up a professional business email for:

  • Affiliate marketing emails
  • Business communication
  • Technical support emails

Therefore, during the Zoho registration process, I selected:

👉 Business Email (Domestic Server)

Figure 1: Applying for a business email on Zoho, selecting Business Email (Domestic Server)
Figure 1: Applying for a business email on Zoho, selecting Business Email (Domestic Server)

⚠️ 2. Critical Turning Point: Entering the Payment Page

After clicking “Register Now,” the system redirected directly to the plan selection page:

  • Paid Standard / Professional editions
  • 15-day trial offered
  • No long-term free plan found

👉 Therefore, I decided to abandon Zoho Mail

Figure 2: After clicking Register Now, automatically redirected to the payment page, decided to abandon Zoho
Figure 2: After clicking Register Now, automatically redirected to the payment page, decided to abandon Zoho

🧭 3. Fallback Plan: Reverting to QQ Business Email

After reverting to QQ Business Email, I completed the basic configuration:

  • Enabled IMAP/SMTP
  • Enabled POP/SMTP
  • Configured SMTP sending service
Figure 3: Reverting to Tencent Business Email, enabling IMAP/SMTP and POP/SMTP services
Figure 3: Reverting to Tencent Business Email, enabling IMAP/SMTP and POP/SMTP services

🧪 4. Problem Occurs: Gmail Sending Failure (Bounced)

When testing sending an email to Gmail:

  • Delivery failed
  • Status showed: Bounced
  • No detailed error message
Figure 4: Clicking on delivery failure only shows "Bounced" with no specific error information
Figure 4: Clicking on delivery failure only shows “Bounced” with no specific error information

🧠 5. Initial Troubleshooting: SPF-Related Issues

During troubleshooting, I discovered:

SPF is used to verify whether the sending domain is trusted

If SPF is not configured, emails may be rejected outright

Figure 5: Found an explanation about SPF while searching in the issue article
Figure 5: Found an explanation about SPF while searching in the issue article

🧩 6. Fix Step One: Adding the SPF Record

Added in Alibaba Cloud DNS:

Bash
v=spf1 include:mail.qq.com ~all
Figure 6: Adding the SPF record in DNS resolution
Figure 6: Adding the SPF record in DNS resolution

🧪 7. Verifying if SPF is Effective

Verification results:

  • SPF resolved successfully
  • DNS took effect
  • But Gmail still bounced the email
Figure 7: Checking with mxtoolbox, confirming DNS is effective but sending still fails
Figure 7: Checking with mxtoolbox, confirming DNS is effective but sending still fails

🔐 8. Discovering the DKIM Configuration Entry

In the QQ Business Email admin console, I found:

👉 DKIM verification feature entry

Figure 8: Discovering the DKIM verification entry in the admin tools
Figure 8: Discovering the DKIM verification entry in the admin tools

🧩 9. Configuring DKIM Signature Information

The system provides:

  • TXT record hostname
  • DKIM public key content
  • DNS configuration instructions
Figure 9: Viewing the DKIM configuration details page
Figure 9: Viewing the DKIM configuration details page

🧪 10. Completing DKIM Configuration and Verifying Successfully

After adding the DKIM record in DNS:

✔ DKIM status changed to “Verified”

Figure 10: After adding DKIM to DNS, the status shows Verified
Figure 10: After adding DKIM to DNS, the status shows Verified

🎉 11. Final Result: Gmail Sending Successful

Re-tested sending emails:

  • Delivery successful
  • No bounce
Figure 11: Sending the email again, the delivery status shows success
Figure 11: Sending the email again, the delivery status shows success

📬 12. Gmail Successfully Received the Email

Final result:

✔ Gmail successfully received the email
✔ Sender is the business domain email
✔ No spam marking

Figure 12: Gmail inbox successfully received the email
Figure 12: Gmail inbox successfully received the email

🧠 13. Final Summary

The core conclusion of this business email configuration is:

❌ Zoho is not a mandatory choice

  • Has a paywall
  • Free path is unclear

❌ The email service itself is not the problem

  • QQ Business Email is completely usable

❗The real key is the email authentication system:

  • SPF (allows sending sources)
  • DKIM (email signature verification)
系列导航

关于作者 · 持续学习与技术实践

我是一名拥有 15 年以上开发经验的技术从业者,自 2013 年起持续运营个人技术博客,记录工作与个人项目中遇到的真实问题,以及解决问题过程中的探索、实践和思考。

除了技术写作,我也在持续开发和维护自己的独立项目,探索新技术和新工具在实际场景中的应用。我始终相信,没有不值得去解决的问题,也没有不值得去学习的技术。

如果这篇文章对你有所帮助,欢迎浏览博客中的其他文章,也欢迎交流技术经验与想法。

关于我  ·  GitHub  ·  邮件联系