If you see a ‘Cannot Open Page’ error, there’s probably something wrong with the internet connection.

An example of an error message:

… because an ssl error has occurred and a secure connection to the server cannot be made. This probably means that you are attempting to connect to the internet via a captive Wi-Fi network (such as in a hotel or airport). A captive Wi-Fi network is one where you have to sign in or take some other action before you can access the internet. To learn more about how to connect to captive Wi-Fi networks, search Apple support for captive Wi-Fi network.

Also, see information about fixing internet connections.