Rooting Unknown Device
To make sure applications can access the root, you may need to enable it from the Developer Options menu in your device's settings. Once in the Developer Options menu, look for the root access option and select from 'Apps only', 'ADB only' and 'Apps and ADB'. You might have to accept a warning about security, too.

If developer settings isn't visible, try the usual method of hitting 'Build Number' several times in the Phone/Tablet Info section in the settings.

Source: I had a problem similar to this after rooting my S3 and installing CyanogenMod 12.