You were installing a program on your computer and suddenly a pop-up window appeared: “The Windows Installer service could not be accessed.” This is a symptom of Windows Installer Error. It maybe due to damaged or missing Windows Installer files.

What is Windows installer?

Windows Installer is the software that allows you to install, maintain, and remove programs on Windows-based systems. The installation process is made easy and consistent with the help of this software.

What is Windows installer error?

The errors which come up while trying to install programs on your computer are called Windows Installer Errors due to which installation fails to complete.

How to fix Windows installer error?

First method

Before jumping into fixing windows installer error, you must first check whether windows installer is enabled or not. If it is disabled, make sure you enable windows installer so that you can install/uninstall an application.

Second method

Another method is to first un-register your Windows Installer and then Re-registering it. To un-register and re-register the Windows installer, tag along the following steps:

1. Click on the start menu.

2. Type “Run” into the search box.

3. Open the “Run” program from the top of the start menu.

4. Type “cmd” in text box and click “OK”.

5. A command prompt screen will appear, type “msiexec/unregister” where the cursor appears and hit “Enter.”

6. Now again click on the start menu and write “Run” in the search field again.

7. Open “Run” search result on the top of start menu.

8. Type “cmd” into the text box again and click “OK”.

9. Command prompt screen appears again and write “msiexec/regserver” where the cursor appears and hit the “Enter” key.
(Note: there will be no visible change in your computer; however, Windows Installer will be un-registered and then re-registered).

10. Restart the computer in order to finalize the process.