Save the file to the desktop as TrustedInstaller.reg.
Exit Registry Editor, and then copy TrustedInstaller.reg to the computer that has the problem.
On the computer that has the problem, run the TrustedInstaller.reg file to update the corrupted registry key with the correct information.
Note When you receive a message that asks whether you want to merge the file with the registry values, click Yes.
Restart the computer.
Restart the Windows Modules Installer service as described in step 1, and then run the Windows Update again.
Step 3: Restore the TrustedInstaller.exe file in C:\Windows\Servicing
If the Windows Modules Installer service still can’t start successfully, the TrustedInstaller.exe file may be missing in the C:\Windows\Servicing folder. To restore the TrustedInstaller.exe file, follow these steps:
Note These steps assume that your operating system is installed on drive C.
Open File Explorer or Windows Explorer.
Type TrustedInstaller.exe in the search field, and then search drive C for the file.
Note You have to include the nonindexed, hidden, and system files during the search.
Select the most current TrustedInstaller.exe file that is located outside the C:\Windows\Servicing folder.
Note You will find this file in different locations on your computer.
Right-click the TrustedInstaller.exe file, and then click Copy.
Paste the TrustedInstaller.exe file into the C:\Windows\Servicing folder.
Note If you receive the "Access Denied" error, make sure that you have full control permission to the C:\Windows\Servicing folder. To do this, follow these steps:
At an elevated command prompt, type the following command, and then press Enter:
takeown /f <Path_And_File_Name>
For example, type takeown /f c:\windows\servicing.
Type the following command, and then press Enter to grant administrators full access to the file:
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