Post date: Nov 12, 2015 4:6:40 PM
After updating to Windows 10, I foolishly tried to view a file in C:\Windows\ImmersiveControlPanel\Search with Notepad. This managed to break the search in control panel function from the Start menu. When clicking on one of the returned results, a window labelled "How do you want to open this file?" shows up instead of the actual control panel item. I searched online, and it seems that this is a known problem, but nobody else has a solution.
After examining the registry accesses with Sysinternals Process Monitor, I figured out the issue: there's an extraneous Open With list setup for the .settingscontent-ms files that the Search feature uses internally; this list prevents the control panel from opening and instead redirects to the Open With dialog.
To fix it, I opened Registry Editor and deleted HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.settingcontent-ms . After testing, searching for both Immersive and Classic control panel entries work again.