Dell XPS 2720 Keyboard, Mouse and Touchscreen Not Working

Hi all,

I have a dell XPS2720 and so here is what happened.  

I installed PS Now app in my PC and i wanted to get my wireless controller to work so I downloaded and installed SCP driver installer. I ran it but then the computer stopped responding so I decided to do a hard reset.  I held the power button to restart then once the computer and windows started, i am unable to do anything anymore since I am stuck in the home screen.  This is the screen wherein when you press any key or click the mouse, the system prompts you to log in your password to unlock the screen.  

My mouse, keyboard and touchscreen are all not responsive.  To isolate the issue, i tried my unifying receiver on another PC and it is working.  I am thinking my drivers perhaps got messed up.

Can you help me?  What can i do given that i can't even log back in to the system.