TLS and Origin Certificate Errors
TLS and origin certificate errors occur when a browser or intermediary service cannot successfully establish or validate a secure connection between the user and the backend server.
These problems typically happen during the HTTPS handshake phase, when encryption keys, certificates, and secure communication rules must be verified before any page content can be delivered.
Common TLS and origin certificate issues
Most TLS errors fall into one of three categories:
- Secure handshake failures
- Certificate validation problems
- Protocol or encrypted transport errors
When these issues occur, browsers or intermediary services may block the connection entirely or return a specific troubleshooting error code.
Related troubleshooting guides
- What 525 SSL Handshake Failed Means and How to Troubleshoot It
- What 526 Invalid SSL Certificate Means and How to Troubleshoot It
- How to Fix ERR_SSL_BAD_RECORD_MAC_ALERT
- How to Fix ERR_HTTP2_PROTOCOL_ERROR
- Browser TLS and Handshake Errors
- Edge and Origin Server Errors
When to use this section
Use these guides when a browser or service indicates that a connection could not be securely established due to TLS negotiation failures, certificate validation problems, or encrypted protocol issues.
If the error instead involves connection failures, DNS issues, or upload problems, check the other troubleshooting collections across the site.