Hello, writing here to get some indications/help about this absurd issue.
Current state: the Windows 10 professional X64 start menu, cortanta, edge, notify area and right clicks on the open apps in the task bar does nothing.
The tablet was updated last year to Windows 10 from 8.1, until june 2017 no problems.
Then seems that an HP automatic software update to the windows system broke the start menu, notifiy and cortana. we rolled back using system configuration and disabled the HP software updates. worked fine for 3 weeks, then windows 10 system downloaded several updates and at next reboot again the start menu, notifiy and cortana broke again.
This time the system restore did not resolve the issue.
So I ran through a windows 10 restore keeping files and app. Nothing, still the issue with the start menu, edge, cortana etc.. Backed up all user files and did a windows 10 clean (no apps or file kept) reinstall through the microsoft tool that re-downloaded the OS image. All went fine for a while, reinstalled the software etc.., then at the next windows 10 update install & configuration run, the issue reappered ! I couldn't believe. I though it was some of the software I installed (antivirus trendmicro, office, acrobat, skype, etc..). So I re-installed windows 10 clean again (no software installed), let all the updates complete and .. again ! start menu, cortanta, edge, notify area broken !
I did everything suggested around on microsoft forums (from signout and reboot, create new user, kill some shell process through powershell, reinstalling apps from powershell, etc..) and dell or other producers forums as well ! but nothing. At this time I gave up with windows 10 and recovered windows 8.1 default and now start menu is working at least. Sigh.
Not sure what this can be related too. "Sfc /scannow" does not report any error.
If I run the microsoft official windows 10 start menu diagnostic cab tool (after a clean install with all windows updates) it gives that "cortana and shell experience something" are not installed correctly. however it cannot fix the issues itself ! in the microsoft forums says to recover the apps, windows etc.. I stopped here. WIndows 8.1 works fine.