What do I need to do to restore several of my Windows 10 app tiles that have grayed out?

[Windows Central Question]

When I try to open the Photos tile for instance, I get the following pop up message:
MicrosoftWindowsPhotos_15.120610020.0_x64_8wekyb3d8bbwe?ms-resource://MicrosoftWindows.Photos/Resources//AppFriendlyName}. Contact your system administrator about repairing or reinstalling it.

I took my laptop to Office Depot, and the tech there worked on this problem for 3 1/2 hours. He said this was the first time someone had brought in a computer with this tile problem.