If you click on an icon and wait 30  sec to a minute, does it eventually respond? This happened with my Compaq (BOO). I fixed it by going to the cache section of Advanced System Settings and changing the cache from being controlled by Windows to a fixed amount of cache, both initial and maximum set to the same value. I have no idea why this worked. This was my only machine NOT using a fixed cache.

A Google search for "windows 10 start menu not working" will produce some results that might help. 

Evaluate for your situation which, if any, of the fixes might be appropriate.

I had the same issue on a Dell Inspiron 15 (5558) recently upgraded from 8.1 to 10, and found the fix using powershell to reinstall the Windows 10 built-in apps fixed the problem.

I did this more than a week ago, and the symptom has not reoccurred. No issues found from running the fix.

BTW, the fix of stopping and restarting Explorer.exe, which I tried first, did not work for me.

Hope this helps.

I had no luck trying this, but thanks for your reply.

The next reply after yours seems promising. Perhaps Microsoft is a better community for W10 specific issues.

Thanks,

Tom

After updating my dell inspiron 13 7000 7348 (2015), the true color application stopped working. No matter how I change the app settings, they just don't take effect. It's like the app isn't there.