Google Translation:
gioia116 wrote:
Good morning, I've had an app for a few years. I never had problems. Today I turned it back on and it won't let me access some websites such as YouTube. I get the message “Safari cannot open the “example” page because it cannot establish a secure connection with the “example” server. How can I solve the problem?
It sounds like you are running an outdated version of macOS which is no longer supported & has been unsupported for a long time.
If your Mac is compatible with a more recent version of macOS, then upgrading the OS may be an option. Depending on which version of macOS your Mac supports, you may still find that Safari is too outdated to connect to many websites today. This means you will need to install a third party web browser such as Firefox, Vivaldi, or Google Chrome, etc. Unfortunately last year, most of these third party browsers announced they will only support the three most recent versions of macOS going forward which at this time are Sonoma, Ventura, and Monterey. Some third party browsers have LTS or Long Term Support versions, so you may find one which is still up to date for some slightly older versions of macOS, but this will only be a temporary measure since sooner or later even those browsers will no longer be compatible as the Internet keeps changing....it may be a year, or several years before they may fail to access various websites.
It really helps if you would post the exact model of your Mac and the version of macOS you are currently using (you should always post this information since it is almost always needed to provide you with the best detailed responses. You can get this information by clicking the Apple menu and selecting "About This Mac".
For example, a 2011 or earlier model Mac has a severely outdated OS which can only be updated to macOS 10.11 or 10.13. A 2012+ model Mac should be able to run macOS 10.15 Catalina & still be able to use third party browsers for the moment.