Surface Pro 4 type cover suddenly not working.

After the firmware update, I did uninstall the Surface typecover from Device Manager (choosing to delete the driver), rebooted and ran a Windows update which pulled the driver down again (don't know if it was a newer version - unfortunately didn't make a note of the version before deleting).

Windows version 1903 with all updates applied.

Hugely surprised it's still working, but definitely firmware related.

Can you please click on the surface type cover properties under device manager> Driver tab > Driver details and post back the name of the drivers you see there. It shows the location where the drivers are saved. Appreciate if you can copy those sys files and post it to some online drive and share with us. Thank you

No apology needed and anyone who doesn't have the same issue think it is a user error or there is a simple workaround. I just wish Microsoft taken the responsibility of their action and fix what they have broken. 

As many did, I also started with simple troubleshooting with the dedicated software (MS has a software to troubleshoot - but that doesn't check for surface keyboard) and then did the restart followed by a factory reset. Here is the steps I've taken so far and everything failed:

1. Disabling and enabling drivers under devices>keyboard and human interfaces. There was no Surface type cover driver anywhere. I also changed the HID driver under human interfaces as there was a second option available. However, that made the HID keyboard device disappear and reverted back to old driver. 
2. Downloaded 2 softwares that check the drivers and push updates and installed all the drivers from there. 
3. Downloaded the driver package for Surface Pro 4 and installed all the msi and exe files available.
4. Troubleshoot with MS software
5. Factory reset 
6. Some people suggested going to BIOS (old method), but now MS upgraded UEFI graphical interface. Keys didn't work
7. Few people said disabling type cover in UEFI>restart and enable type cover in UEFI again>restart. This method didn't work, but I am being hopeful doing this every time I install a new firmware or doing a factory reset
8. A youtube genius said the ports need to be cleaned. Cleaned the ports with rubbing alcohol
9. Upgraded to the latest v1903 from v1809 and waited whole night installing all the software updates following the installation.
10. There we general HID fixes released by MS for v1803. Downgraded to 1803 using the USB drive, manually downloaded all the required 
11. There was a specific type cover fix released with v1709 and this time deleted all the partitions (not the system partition which can't be erased) and installed the software. Manually downloaded the March 2018 fix and installed. From the installed all the updates (Microsoft doesn't allow to install the final update and it had to from v1709>1803>1809 and then finally 1903. After this update I tried to install all possible KB updates available did many resets, again went back and forth between drivers, but nothing was useful
12. Enabled developer mode > enabled device portal and device discovery settings. I was very hopeful.
13. Yesterday registered for Windows Insider Program and subscribed for driver, apps and other updates. After this update took around 6 hours and software update screen was different than usual. When the device was booted, I pressed the keyboard and there were flickering on the screen and then again nothing worked. Installed all the available updates (There were around 30 updates, including the drivers). But nothing so far.

Now the next option is to add the related sys files for type cover into Windows>system32>Drivers so that these will appear in device manager. Appreciate if you can copy those sys files from your device and post for us to test. You can see the file names and the location of these files by clicking on the properties of the driver from device manager>drivers

Thank you!

I apologize if I sounded aloof or condescending.  That was the farthest thing from my mind.  My troubleshooting philosophy has always been to do the simplest fixes first and gradually getting more radical.  I wholeheartedly agree that something this simple shouldn't take a complete wipe and rebuild.  It was also a bad choice of words to seem to condemn what isn't Microsoft.  Microsoft has the same problem we do because sometimes, I think, their right hand has no clue what their left is doing and saying.  I was only saying that it is easier to get a problem solved when the problem belongs to only one company but they, too, like to hide behind the corporate shield.  To me that's a damn shame because greed is not the lubricant this industry needs.  Damn, after 26 years in the military starting in 'Nam, I sound like a hippie peace freak.

Paul

I appreciate if anyone can post, surface type cover sys file from C:/Windows/System32/Drivers. 

In my case I see two drivers related to keyboard 

1. kbdclass.sys
2. kbdhid.sys

If you have working type cover, go to devices > expand keyboard > double tap surface type cover. Click on driver details, it shows the sys files related to type cover and the location where these sys files are saved. Please copy to some drives like dropbox and share the link. I believe we might be able to fix the issue by using these driver files

My Surface Pro 4 keyboard stopped working in September last year and I'd pretty much given up on it.

However, since the last firmware update, it is now working again and hasn't skipped a beat the last 3 weeks.

After the firmware update, I did uninstall the Surface typecover from Device Manager (choosing to delete the driver), rebooted and ran a Windows update which pulled the driver down again (don't know if it was a newer version - unfortunately didn't make a note of the version before deleting).

Windows version 1903 with all updates applied.

Hugely surprised it's still working, but definitely firmware related.