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

I'm having this same exact issue. I'm using a Bluetooth keyboard and an HP x4000b Bluetooth Mouse on my Dell Venue 8 Pro (Windows 10 Build 9926). It started with the mouse not working, but now as soon as I connect the devices, they both immediately disconnect and stop working. I've tried restarting the computer, reinstalling all Bluetooth drivers, reconnecting the devices, and updating using Windows Update. Both devices were working perfectly at 3:00 PM EST yesterday.

Any help would be greatly appreciated!

UPDATE!!!

Tried everything I could think off to get the Mouse and Keyboard to work but still nothing. I have Teamviewer on all my devices so I connected with my computer (that works) to the computer with w10 on it. W10 had the sign in screen on so from my remote computer I logged into the W10 computer. I can control the W10 from the remote computer with Keyboard and Mouse, tried to reinstall drivers for M&K but keep on getting an error message. This is the message I get from the device manger:

This device cannot start. (Code 10)

Insufficient system resources exist to complete the API.

Scott

Same problem after upgrading to Windows 10 insider preview, before I had windows 8.1 pro x64. I have a logitech wireless keyboard and mouse. Came up with a solution - power off your pc. Then disconnect your keyboard and mouse. If its a wireless then unplug the wireless key, wired then unplug the usb/ps2 cable. Now power on your pc and wait till login screen. Again power off your pc by pushing the power button. Now connect the keyboard and mouse. Power on your pc and it will detect now. Atleast worked for me.

I am having this exact same problem with my Logitech Revolution MX 5500 wireless keyboard and mouse.  I upgraded from Windows 7 to Windows 10 on my desktop PC and neither the wireless keyboard or mouse works when I get to the Windows logon screen after I power it on or restart.  So, I have to unplug the USB wireless dongle and plug it back in while on the logon screen and the mouse and keyboard will work until the next reboot/power off/on.

I tried a wired keyboard and mouse and they worked just fine.  So this issue has to do specifically with the wireless keyboard and mouse.

This solution sounded promising to me.  But...  When I power on my PC w/o any keyboard plugged in, I get a message from the BIOS saying "Keyboard error or no keyboard present".  So, I plugged the USB dongle back in and hit the reset button and the mouse and keyboard worked when I got to the logon screen.  However, they no longer worked after another reboot.

I also tried uninstalling all of the USB devices under Human Interface Devices and the Mouse and Keyboard from Device Manager (using a corded mouse) and the wireless mouse and keyboard and rebooted.  The keyboard and mouse worked at the logon screen again

• but only until I rebooted as before.

I also spent about 2 hours on the phone with an offshore support person from Logitech and was not able to solve this issue.  It is now being escalated to level 2 and I am waiting for a call back.

Fortunately this is not a huge problem as the work around is relatively easy (just unplug the USB wireless dongle and plug it back in).  It sure is a heck of a nuisance though!  To make it slightly less of a nuisance, I plugged my USB wireless dongle into a USB extension wire so that I could have the dongle on top of my desk (rather than plugged into the back of the computer on the floor!)  

I hope this issue gets resolved soon!

Ok I'm 90% sure I found the issue. For me at least, my Bluetooth HID Device driver is stuck with the "Allow Windows to turn this device off to save power" option on. When I try to disable it, I get the blue screen of death with the following error: KMODE_EXCEPTION_NOT_HANDLED (HIDClass.sys)

I expect the issue might be similar for all of you.

Control Pane> Devices and Printers

Right click on you mouse or keyboard, hit properties.

Go to the hardware tab, click on the HID Device, click properties.

Click on Change Settings, go to the Power Management Tab.

The "Allow Windows to turn this device off to save power" should be checked.

If you uncheck it and press OK you should get the error mentioned above.

If I'm right, the devs should be able to fix it in the next update.

-Cheers! :D