ContributionsMost RecentMost LikesSolutionsRe: Windows 10 - Critical Error - Start Menu and Cortana aren't working The following process will require you to edit the Windows registry! If you right-click on the "Start" button (bottom left keyboard) and the menu comes up: click on the "run" command. If you right-click on the "Start" button (bottom left keyboard) and the menu DOES NOT come up, do the following: A. Bring up the task manager (ctrl+alt+delete) B. Click on "File" (top left keyboard) then click on "Run New Task" 1- Type "regedit" into the box labeled "Open" and click "OK". (for either of the above scenarios) 2- Go to path [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WpnUserService]. 3- Double-click on "Start" on the right side of the screen. 4- Change the value data to "4" with "Base" set to "Hexadecimal" then "OK". 5- Reboot. Note backup first your current registry before doing a modification. Check other methods here. https://www.errorsolutions.tech/error/windows-10-start-menu-critical-error/