Windows 11 Explorer and Taskbar Issues

Follow these steps in this order, and then reboot your computer:

1.) Download Windows 10 ISO Image to "C:\Win11_English_x64.iso"
2.) Download and Install WinRAR: https://www.win-rar.com/download.html?&L=0
3.) Extract ISO Image to "C:\Win11_English_x64"

4.) Start Powershell -> Start Menu -> Run -> taskmgr -> File -> Run new Task -> %SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe -> Select "Create this task with administrative privileges." -> Click OK.

Change the execution policy so you can run scripts locally:
5.) Set-ExecutionPolicy -ExecutionPolicy Bypass -Scope LocalMachine -Force;

Use any one of these to verify which edition of Windows 11 you have installed:

6A.) Get-ComputerInfo -Property Windows*
6B.) Get-ComputerInfo | select WindowsProductName, WindowsVersion, OsHardwareAbstractionLayer
6C.) systeminfo /fo csv | ConvertFrom-Csv | select OS*, System*, Hotfix* | Format-List
6D.) (Get-WmiObject -class Win32_OperatingSystem).Caption
6E.) [System.Environment]::OSVersion.Version
6F.) [Environment]::OSVersion
6G.) winver
6H.) systeminfo

Make sure to select the index in the ISO image, based on the Edition of Windows you have currently installed:

7.) DISM /Get-WimInfo /WimFile:"C:\Win11_English_x64\sources\install.wim"

Details for image : C:\Win11_English_x64\sources\install.wim

Index : 1
Name : Windows 11 Home
Description : Windows 11 Home
Size : 15,854,479,870 bytes

Index : 4
Name : Windows 11 Education
Description : Windows 11 Education
Size : 16,136,983,252 bytes

Index : 6
Name : Windows 11 Pro
Description : Windows 11 Pro
Size : 16,134,043,048 bytes

Index : 8
Name : Windows 11 Pro Education
Description : Windows 11 Pro Education
Size : 16,136,934,462 bytes

----------**********----------**********----------**********
**********----------**********----------**********----------

If you have Windows 11 Home, the index is set to 1...

If that is the correct Index, then Restore the running operating system image with the ISO you previously extracted:
8.) DISM /Online /Cleanup-Image /RestoreHealth /Source:C:\Win11_English_x64\sources\install.wim:1 /LimitAccess

Cleanup the component store, remove superseded components, finalize patches:
9.) DISM /Online /Cleanup-Image /StartComponentCleanup /ResetBase

Scan to replace any obsolete, corrupt, or missing files:
10.) ./SFC /SCANNOW

Reinstall ALL Apps first:
11.) Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"};

Reset All Apps:
12.) Get-AppxPackage | Reset-AppxPackage;

Run this in Powershell to reverse the Start Menu / Taskbar changes:

13.) Set-ItemProperty -Path "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Shell\Update\Packages" -Name "UndockingDisabled" -Value "00000000"
14.) Set-ItemProperty -Path "HKCU:\Software\Microsoft\Windows\CurrentVersion\Search" -Name "SearchboxTaskbarMode" -Value "00000001";
15.) Set-ItemProperty -Path "HKCU:\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer" -Name "NoTaskGrouping" -Value "00000000";

Restart Explorer to see the taskbar changes:

16.) ./taskkill /f /im explorer.exe;
17.) ./CMD /Q /C START /REALTIME explorer.exe;

18.) Run Windows Update (Settings -> Windows Update)

Remove superseded components, and finalize the image:
19.) DISM /Online /Cleanup-Image /StartComponentCleanup /ResetBase

Scan to replace any obsolete, corrupt, or missing files:
20.) ./SFC /SCANNOW

The start menu problem is resolved by the KB5006746 upgrade.

Same Issue. I solved it by opening "Control" and change the date to a future day and restart.