Windows 10 Start menu, notification center, store apps not working

Everything in Windows 10 worked perfectly for just 3 or 4 days after upgrading from 8.1. Yesterday I wanted to use the search feature, so I press win+s and get the error "Critical Error: Your Start menu isn't working. We'll try to fix it the next time you sign in."

(I also can't open the settings app since that's also a 'metro' app)

I have tried everything I could find and nothing worked for me.

Things I've tried include:

• In powershell:

   Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}
  

• The answer here.

And things like that.

"Did you modify the registry?"

Yes:

• Adding Sublime Text 3 to the "Open with" list (It can't be because of this can it?)

• Back in Windows 8; Adding a few things to the RMB menu of some files (no trouble at all)

So what can I do to fix these problems?

A solution posted by Loopey:

1. Login to your current profile
2. Press Win+X, and select "Command Prompt (Admin)"

3. Enter the following commands, in this order

   1. net user "TempAdmin1" "password1" /add
   2. net user "TempAdmin2" "password2" /add
   3. net localgroup administrators "TempAdmin2" /add

4. Press Ctrl+Alt+Del, click Sign Out

5. Login to the "TempAdmin1" account using password "password1"
6. Logout, and then login to the "TempAdmin2" account, using "password2" (note: you must fully sign out, not just switch users)
7. Open File Explorer, select View, then check the box marked "Hidden Items"
8. Directly navigate to C:\Users\TempAdmin1\AppData\Local\TileDataLayer by typing it in the address bar. (click "continue" to gain access when prompted)
9. Right Click the folder "Database" & Copy
10. Now, navigate to the same folder for your damaged profile (C:\Users\YOUR_USERNAME\AppData\Local\TileDataLayer)
11. Right click "Database", and rename to "Database.BAD"
12. Right click empty area in the folder, and select Paste
13. Reboot, then sign back in with your original profile.

Now, assuming all is well, you want to delete the two accounts you created:

1. Win+X → Control Panel → User Accounts → Manage Another Account
2. Select Account, then "Delete Account"

Brief explanation:

1. Your TileDataLayer database is damaged
2. You need a new TileDataLayer database
3. Create a new user (user A), and login with it (a new database will be created). Proceed with this procedure only if the Start Menu and all other apps are working correctly as user A.
4. Because the database is locked when you're logged in, you create user B (with access to user A's profile and your user profile)
5. Rename the old database, and copy the new database from user A to your profile
6. Logout from user B, and your account should work again

Here are some fixes I found online:

Fix One:

• Right-click at Start and run Command Prompt as admin
• Type command:
• ren %windir%\System32\AppLocker\Plugin*.* *.bak
• Reboot

Fix Two:

• Right-click at Start and click Run
• Type services.msc and press the Enter key
• Right click on Application Identity and select Start
• Reboot

Fix Three:

• Right click on the Start button and select Command Prompt (Run as administrator)
• Type dism /online /cleanup-image /restorehealth
• Reboot

Fix Four:

• Press (Windows key)+R on your keyboard.
• Key in PowerShell and hit Enter.
• Right click on the PowerShell icon on the taskbar and select Run as administrator. (Or create a shortcut with PowerShell and run as admin.)

• Now paste the following command in the Administrator: Windows PowerShell window and press the Enter key:

  Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register “$($_.InstallLocation)\AppXManifest.xml”}

• Wait for PowerShell to execute and complete the command. Ignore the few errors (in red color) that may pop up.

• Reboot.

None of these fixes worked for me, but I hope they may work for someone. I did do a restore point recovery, however; that worked. But I'm going to swap back to Windows 7 for the time being, as some of my other programs do not work properly either.

A good solution can be find in here.

Solution 1: (Chris Raisin)

Create a file with the following code:

@echo off
cd %SystemDirectory%
Taskkill /F /IM Runtimebroker.exe > nul
RuntimeBroker.exe

Save it as a .cmd file, for instance FixLockedDesktopProcs.cmd and run it as administrator.

Solution 2: (Robert Gavick)

This is a problem associated with Dropbox. The best way to solve the “Critical Error” message is to uninstall the Dropbox application.

1. Launch control panel (right click on the start menu)
2. Go to the Programs.
3. Uninstall Dropbox
4. Reboot.

Now the menu, search and cortana should work normally. You can re-install Dropbox app now but remember to disable the launch of Dropbox at the Windows start.