First, make sure the computer has no internet connection. Not via Ethernet or WiFi, then reboot. If that doesn't fix it, again while no internet is connected, try the following...
1. Power off the laptop.
2. Power on the laptop.
3. As soon as you see the rotating loading circle, press and hold the Power Button until the computer shuts off.
4. Repeat this process a few times until you see the "Preparing Automatic Repair" screen.
5. Now you want to let the laptop boot to the "Automatic Repair" screen.
6. Click "Advanced Options" and then select "Troubleshoot".
7. Here you want to select "Refresh your PC", if you do not wish to erase data, or "Reset your PC" to erase all data and restore your system.
8. From here just follow the screen...