Unable to access Windows Installer Service

The Windows Installer Service is necessary for installing new software. The Windows Installer Service aims to improve the process of installing and uninstalling programs. If the Windows Installer Service has been stopped, fresh installations will be unable to access the Windows Installer Service to begin the installation procedure. This may happen if a new version of the Windows Installer Service has been installed, and has to be started manually. To solve the problem, the Windows Installer Service has to be started. The Windows Installer Service can be started from the Services and Applications tab of the Windows operating system.


I have a problem when downloading updated software, including MSN and iTunes.
When I want to update my Windows program reference, an error message occurs:
"Unable to access Windows Installer Service. This can occur if Windows is in Safe Mode, or if the Windows Installer is not installed. Contact your support personnel for assistance."
I checked, I am not in safe mode, I restart Windows in Normal mode.
What should I do to be able to place my updates?


To solve this:

  • Right-click on "My Computer"
  • Click "Manage"
  • Open "Services and Applications"
  • Click on "Services"
  • Select "Windows Services" on the right pane
  • Right-click on it and then click on "Start"


Thanks to Baalan for this tip.
Published by aakai1056. Latest update on March 16, 2012 at 02:05 PM by Celia Gatward.
This document, titled "Unable to access Windows Installer Service," is available under the Creative Commons license. Any copy, reuse, or modification of the content should be sufficiently credited to CCM (https://ccm.net/).
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