Google suggests the following, sorry for the poor formatting:
The net::ERR_CERT_AUTHORITY_INVALID error means Opera does not trust the issuer of the website's Let's Encrypt SSL certificate. This is usually caused by your operating system having an outdated certificate store, an incorrect system clock, or interference from third-party security software.Troubleshoot this issue with the following steps, ordered from easiest to most thorough:1. Fix Your Date and TimeIf your computer's date or time is incorrect, it cannot verify the validity period of an SSL certificate.Windows: Right-click the clock in your taskbar, select Adjust date/time, and toggle on Set time automatically.macOS: Open System Settings > General > Date & Time, and turn on Set date and time automatically.2. Update Your Operating SystemLet's Encrypt relies on specific root certificates that are bundled with your system. If your device is outdated, it may lack the ISRG Root X1 certificate required to validate the connection.Windows: Go to Settings > Update & Security (or Windows Update) and install any pending updates.macOS: Go to System Settings > General > Software Update to check for macOS updates.3. Check Antivirus and VPN InterferenceSome antivirus or VPN suites use "SSL Scanning" or firewalls that intercept your traffic and replace Let's Encrypt certificates with their own.Temporarily disable your VPN or the "Web Shield"/"HTTPS Scanning" features in your antivirus. If the site loads, adjust the settings in your security software.4. Clear Browser DataCorrupted cache or stored SSL certificates in Opera can cause persistent errors.In Opera, press Ctrl + Shift + Delete (or Cmd + Shift + Delete on Mac).Set the time range to All time.Check Cached images and files and Cookies and other site data.Click Clear data.
Topic: Re: Problem on HF-U : net::ERR_CERT_AUTHORITY_INVALID (Read 3495 times)