Firefox Secure Connection Failed
Warningfirefox
Overview
Firefox "Secure Connection Failed" means the browser cannot negotiate a secure TLS connection with the server.
Key Details
- SSL_ERROR_* prefix in the error code
- TLS handshake failed between Firefox and server
- Server may support only outdated TLS versions
- Firefox enforces minimum TLS 1.2
Common Causes
- Server only supports TLS 1.0 or 1.1 (deprecated)
- Server cipher suite incompatible with Firefox
- SSL certificate configuration error
- Network appliance interfering with TLS
Steps
- 1Check if the site works in another browser
- 2Temporarily lower TLS minimum: about:config > security.tls.version.min (not recommended)
- 3Disable HTTPS-Only mode temporarily
- 4Check for VPN or proxy TLS interference
Tags
browserfirefoxfirefox secure connection failedfixtroubleshooting
More in Firefox
Frequently Asked Questions
TLS 1.0 and 1.1 have known security vulnerabilities and were deprecated in 2020.