I had a smooth transition upgrading from Windows 7 to Windows 10. That was however short lived. After updating my browser, I did a system restart. Things went to hell after that. All of a sudden, left clicking the Windows icon, Cortana icon or the Notification icon did nothing. Microsoft Edge Icon disappeared off the task bar. With the help of a friend we found that ShellExperienceHost.exe was not running in Task Manager. After running the exe file Left click on Window and Notification icon brought up their menus. Cortana still did not work. Nor, could you access search. We also tried running the following string in power shell.

Get-appxpackage -all *shellexperience* -packagetype bundle |% {add-appxpackage -register -disabledevelopmentmode ($_.installlocation + \appxmetadata\appxbundlemanifest.xml)}

It worked once and everything seemed fine. However, last night I did a system restart because programs started to lockup and the task bar occasionally flickered. I also tried a restart of Windows Explorer but that did not help either. Anyway, now none of that stuff works again and the steps we took to get them to work last time do nothing now. I also tried to do a restore back 2 days. That also failed . apparently there was an error with some files. I am a novice at this stuff so I really could use some help.