Android devices with a wrong system clock, or an old WebView, reject otherwise valid certificates during the handshake.
Android devices with a wrong system clock, or an old WebView, reject otherwise valid certificates during the handshake.
Set date and time to automatic, update Android System WebView from the Play Store, then clear Chrome's cache. Test the same URL on mobile data to rule out a captive-portal Wi-Fi network.
Android has its own failure mode, but ERR_SSL_PROTOCOL_ERROR has a wider set of causes. The most common one overall is: The server only offers TLS 1.0 or TLS 1.1, which every current browser has disabled.
Enable TLS 1.2 and TLS 1.3 on the origin and remove the deprecated versions. On nginx set `ssl_protocols TLSv1.2 TLSv1.3;` and reload.
The SSL checker reads the live handshake: protocol versions offered, cipher suites, chain completeness and expiry. If it cannot complete the handshake either, the fault is server-side and not your browser.
Android devices with a wrong system clock, or an old WebView, reject otherwise valid certificates during the handshake.
Set date and time to automatic, update Android System WebView from the Play Store, then clear Chrome's cache. Test the same URL on mobile data to rule out a captive-portal Wi-Fi network.
Chrome tried to start an encrypted connection and the server answered with something that is not valid TLS. In almost every case the server is offering a protocol version or cipher the browser refuses, the certificate is broken, or something on the network is intercepting the handshake.