The Email Delivery Tracing tool in cPanel shows the delivery status of outgoing and incoming messages — whether they were delivered, deferred, queued, or rejected. This is the fastest way to diagnose why an email did not arrive.
Run a delivery trace
- Log in at https://tpc-hosting.com/login and open cPanel.
- Under Email, click Track Delivery.
- In the search field, enter the sender's address, the recipient's address, or leave it blank to see all recent messages.
- Click Run Report.
- The results show each message with:
- Sender and recipient address
- Time the message was processed
- Result: Delivered, Deferred, In queue, or Failed
- Click the + icon next to any message to expand the full delivery log, including SMTP response codes and error messages from the receiving server.
Understanding delivery results
- Delivered — the message was accepted by the receiving server. If the recipient still did not get it, the problem is on their end (spam folder, client filter).
- Deferred — the receiving server temporarily refused the message. cPanel will retry automatically. Common cause: receiving server was busy or temporarily unavailable.
- In queue — the message is waiting to be sent. If stuck for more than a few minutes, the receiving server may be unreachable.
- Failed — the message was permanently rejected. Read the error in the expanded log — it usually contains the exact reason (e.g., blacklisted IP, invalid recipient, rejected by spam filter).
Common error codes
- 550 — recipient does not exist or the domain is rejecting your mail
- 554 — message rejected due to spam policies (often an IP blacklisting issue)
- 421 — temporary rejection, will be retried
- 452 — receiving server is out of storage space
If you see a blacklist-related rejection in the log, refer to our article: Why Are My Emails Being Blocked and How to Improve Deliverability.
