Samsung Z3 in
You can try the following:
1. Restart the phone;
2. Uninstall recently installed third-party software, reboot the phone;
3, after the backup phone data (phone book, SMS messages, multimedia information, etc.), restore the phone to factory settings: Set - Privacy - restore factory settings;
4, in my equipment, the main screen mode, choose Easy mode re-election back to standard mode.
If the problem persists, it may be the system or hardware problems, we recommend that you experience this problem, contact a Samsung Service Center friends for testing, in addition to a unified Xiao Bian also remind you please do not restart the phone when to press the Menu key, because the press safe mode enables live the Menu key.