Here are some troubleshooting steps you can try.
- First is to do a hard reset, remove the battery and AC adapter then press and hold the power button for 20 seconds the try if it will boot up normally.
- If that doesn't work try to load it into Safe Mode, while the laptop is booting up repeatedly press on F8, you can stop tapping once Advanced Boot Option is open.
- Select Safe Mode then press Enter. Once in Safe Mode disable all your startup items in Task Manager then reboot your laptop.
- If all these will not work you may need to run a Factory Reset using the built in Factory Image in your laptop or using a System Recovery disc.