Mouse and keyboard input not working after windows 10 upgrade from windows 7.

i found a solution to the problem, although i cannot recall too clearly how i fixed it. 

1. go to settings 
2. click on devices ( bluetooths printer mouse )
3. scroll down on the right side until you see " related settings " and click on device and printers 
4. once you are there you should see devices , printers , and another option below printers.
5. there should be something labled as usb controller or something similar.
6. you have to select that device and go to the hardware tab
7. click on properties 
8. go down to change settings 
9. go to the driver tab 
10. uninstall the driver
11. restart the computer when you are asked to 
12. should be fixed

i believe that the port for the usb mouse was being used by whatever that controller was and after you uninstall it, then the usb mouse should work.

I had the same problem. This started when I couldn't use two fingers to scroll the touch pad as i used too, i tried Elan Drivers, and when they didn't work. I attempted to install them. I ended up here.

I connected an external mouse, then i went to Device Manager, i could see the keyboard and mouse with a driver "Lenovo Ps2 something"... 

I uninstalled this drivers, for both the mouse and the keyboard, then set an automatic scan online for new hardware devices and drivers. This fized my problems. Hope you find this useful too.

I upgraded to the window 10 tech preview from windows 7 and now my mouse and keyboard dont work once the os loads up and brings me to the sign in screen. I cant even roll back to windows 7 now because I have no mouse input except for when the bios splash screen is showing. Any help would be amazing thankyou.

Windows 10 has been working fine on our DELL XPS All in One until a critical Windows update was installed on 8/23/15.  As soon as it come up from this update the wireless logitech keyboard stopped working.  Because it is a touchscreen it is possible to do troubleshooting without the keyboard.

Similar to others on here.  The keyboard works up until after you log into the home screen and it loads your profile.  

I tried to perform system restore to the 8/23 point but the issue was exactly the same.  

If you open the unifying software from logitech you can see the keyboard is there.  It even flashes an orange asterisks when you type on it indicating that it is properly talking with the computer.  The issue is that Windows just won't allow it to actually accept any typing in any field.  

Microsoft really needs to address this with an official response.