How to troubleshoot Windows Installer errors

Applies to: Windows 7 EnterpriseWindows 7 Home BasicWindows 7 Home Premium


When you install, uninstall, or update a program on a Windows-based computer, you may receive one of the following error messages.
Error message 1
The Windows Installer Service could not be accessed.
Error message 2
Windows Installer Service couldn't be started.
Error message 3
Could not start the Windows Installer service on Local Computer. Error 5: Access is denied.


To fix this problem automatically, run the "Fix problems that programs cannot be installed or uninstalled" troubleshooter to repair issues that block program installation or removal because of corrupted registry keys.
Important To perform many of the methods and steps in this article, you must be logged on to your computer as an administrator.
To determine whether you're using an account that has administrator rights
After you've verified that you're logged on to your computer as an administrator, you can start troubleshooting Windows Installer issues.

More Information

For general information about how to install or to uninstall a program, see the following: