Network error occurred: how to fix it on Android

It may happen that your smartphone loses internet access overnight, after being switched off, without any modification made to the network settings. You will notice, however, that some applications are still able to download data, while others won't synchronize.

How to reset your network settings?

You can always restore the default network settings of your phone!
Please note that your personal data won't be deleted during this manipulation:
From the HomeScreen, go to Menu, select Settings, then Wireless & networks. From there, tap Mobile networks, next Access Points, and Menu. Once this is done, choose Restore default settings.
It is possible that at this stage the network still does not work ... So read the following.

How and why do you need to set the date/time?

To communicate properly, your smartphone and servers will need to provide information about the current time and date (for example, check whether your request has expired). This is particularly necessary for app synchronization.
From the Homescreen, go to Settings, select More, and choose Date and Time.
Check Automatic date and Time to make use of the network-provided time.