Why can't I access the Windows Installer service

Q: Under Windows XP, when I run the MSI installer, I can't access the Windows Installer service. How can I solve it?
A: If this is not the case under "Safe Mode", it is probably due to “Windows Installer” service is disabled. Run “services.msc”, find the service "Windows Installer", double click to open its properties. Then select “Manual” in the “Startup Type“ drop-down box on the "General" tab, and finally click the “Start” button to start the service. If you are prompted at this time that the specified service has been marked as deleted, or other errors, the service cannot be started, you will need to reinstall Windows Installer.
1. Windows XP users can go to
2. Windows 2000 users can go to
to try the following methods:
First, run the %systemroot%\\system32\\msiexec.exe /unregserver command to Uninstall “Windows Installer” service. Then use WinRAR and other decompression tools to open and unzip the InstMsiW.exe you just downloaded. Go to the unzipped folder, right-click msi.inf and mspatcha.inf, and select “Install”. (note the order). Run the %systemroot%\\system32\\msiexec.exe /unregserver command to install the “Windows Installer” service.