Windows Modules Installer (TrustedInstaller) Service Defaults in Windows 7

Enables installation, modification, and removal of Windows updates and optional components. If this service is disabled, install or uninstall of Windows updates might fail for your computer.

Default Settings

Startup type:
Windows 7 StarterAutomatic
Windows 7 Home BasicManual
Windows 7 Home PremiumManual
Windows 7 ProfessionalManual
Windows 7 UltimateManual
Windows 7 EnterpriseManual
Windows 7 Starter SP1Manual
Windows 7 Home Basic SP1Manual
Windows 7 Home Premium SP1Manual
Windows 7 Professional SP1Manual
Windows 7 Ultimate SP1Manual
Windows 7 Enterprise SP1Manual
Display name:Windows Modules Installer
Service name:TrustedInstaller
Service type:own
Error control:normal
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TrustedInstaller

Default Behavior

Windows Modules Installer is a Win32 service. It is starting automatically on the operating system startup in Windows 7 Starter SP0. This service won't be started if the user doesn't start it in Windows 7 Home Basic SP0, Windows 7 Home Premium SP0, Windows 7 Professional SP0, Windows 7 Ultimate SP0, Windows 7 Enterprise SP0, all editions of Windows 7 SP1.

When the Windows Modules Installer service is started, it is running as localSystem in its own process of TrustedInstaller.exe. If Windows Modules Installer fails to start, Windows 7 attempts to write the failure details into Event Log. Then Windows 7 startup should proceed and the user should be notified that the TrustedInstaller service is not running because of the error.

Restore Default Startup Configuration of Windows Modules Installer

1. Run the Command Prompt as an administrator.

2. Depending on the version of your operating system, copy the commands below, paste them into the command window and press ENTER.

For Windows 7 SP0 Home Basic, Windows 7 SP0 Enterprise, Windows 7 SP0 Home Premium, Windows 7 SP0 Professional, Windows 7 SP0 Ultimate, Windows 7 SP1 Home Basic, Windows 7 SP1 Enterprise, Windows 7 SP1 Home Premium, Windows 7 SP1 Professional, Windows 7 SP1 Starter, Windows 7 SP1 Ultimate:
sc config TrustedInstaller start= demand

For Windows 7 SP0 Starter:
sc config TrustedInstaller start= auto
sc start TrustedInstaller

3. Close the command window and restart the computer.

The TrustedInstaller service is using the TrustedInstaller.exe file that is located in the C:\Windows\servicing directory. If the file is removed or corrupted, read this article to restore its original version from Windows 7 installation media.