154PasswordsWhen enabled, password characters display briefly as youtap them while entering passwords.1. From the (Settings) screen, tap Security.2. Tap Make passwords visible to enable or disable briefdisplays of password characters.Device Administration1. From the (Settings) screen, tap Security.2. To add or remove device administrators, tap Deviceadministrators.3. To enable or disable installation of non-Google Playapplications, tap Unknown sources.An informational pop-up displays.Read the message and tap OK to allow installation ofnon-Google Play applications.Warning! Enabling this option causes your tablet and personaldata to be more vulnerable to attack by applicationsfrom unknown sources.4. Tap Verify apps to block or warn before installing appsthat may cause harm to the device.Credential StorageTrusted CredentialsIf a certificate authority (CA) certificate gets compromised orfor some other reason you do not trust it, you can disable orremove it.1. From the (Settings) screen, tap Security.2. Tap Trusted credentials.The trusted credentials screen has two tabs:• System: Displays CA certificates that are permanently installedin the ROM of your device.• User: Displays any CA certificates that you installed, forexample, in the process of installing a client certificate.3. Tap a CA certificate to examine its details.A scrolling screen displays the details.4. Scroll to the bottom of the details screen and tap Turnoff to disable a System certificate.Caution! When you disable a system CA certificate, theTurn off button changes to Turn on, so you can enablethe certificate again, if necessary.5. Tap OK to return to the certificate list.
