1. Check whether the Unknown Source setting is turned on.
2. Check whether the machine supports the downloaded software format. The software format supported by Android phones is. APK format.
3. Please read the software details when downloading the software to see if there are any requirements for the machine operating system.
4. If you still can't install the software/game, it may be because the software version is low or there are compatibility problems between the software version and the system. It is recommended to download a new version and try to install it;
5. If it is invalid, back up the data (contacts, information, photos, etc. ) and try to restore the factory settings.
If the problem still exists, please take the purchase invoice, maintenance card and machine to the service center, and the professional after-sales engineer will help you test it.