If you can connect and use an external mouse and keyboard, please perform the below mentioned steps:
1. Please start the computer and enter System Setup (BIOS). To enter System Setup hit the F2 when the computer starts.
2. Restore System Setup fields to Defaults.
3. Shut down the computer and disconnect Battery, AC Adapter and external devices.
4. Press and hold the power button for 10-15 seconds and then release the power button.
5. Re-connect the AC Adapter and Battery only and power on the computer.
6. Reboot the computer to Safe Mode.
7. When computer boots press and hold "Windows key" on the keyboard and press the key "R".
8. Run dialog box will be displayed.
9. Type "devmgmt.msc" (without quotations marks) and hit Enter.
10. Expand "Keyboards", right click the listed keyboard(s) and select "Uninstall".
11. Repeat step 10 for "Mice and other pointing devices".
12. Restart the computer and wait for the keyboard and mouse drivers to load.
13. Check the functionality of the keyboard and mouse now.
Hope this helps.
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