I recently did a clean install of Windows 10 on my primary workstation. After installing most of my apps again, I noticed that the search function in the Start Menu was only finding some of the applications I had installed. Instead of clicking on shortcuts to launch applications, I’ve grown accustomed to using Windows Key to search for the app I want to launch; a habit that stems from my time spent on a Mac using Command-Space bar to search for and launch applications. Not being able to find every app that is installed was very annoying; also puzzling since I had just done a clean install of Windows. In googling this problem, I found different answers regarding rebuilding the index cache, checking the Windows Search service, reinstalling Cortana, or deleting some registry key. I didn’t find a solution until I stumbled onto this Reddit thread – apparently if you disable background apps under Settings > Privacy > Background apps it prevents Windows Search from working correctly.
Funny enough, this answer is in the first result from my Google search above but I didn’t see it until I wrote this post; I just never bothered to scroll down far enough.