How to turn off Huawei Mobile Phone 1 Certificate Authority Center Open Settings 2 Click Security and Privacy 3 to enter the interface, and then click More Security Settings 4 to enter the interface. After entering the interface, click the two sliders at the icon positions of "Download applications from unknown sources" and "Install external application sources" in the list to turn off these two functions 5. After the function is turned off, it is displayed as an icon, and the setting is successful.