Windows installer service could not be accessed actually an element from Microsoft. It is generally used for installing any program, maintenance and also for the uninstallation. So, this is the reason you are getting the said error while installing and uninstalling a program. Although, while you are getting this notification you won’t be able to install or uninstall any software, there are ways fix the error so that, you may not come across it next time you install a program.

Reasons Behind the Error
Windows installer service could not be accessed; this error occurs while installing or uninstalling a program as the Windows Installer has not been installed properly. It is also true that, if the Windows Installer files or folders are damaged or missing, the error could still appear. Well, the failure could also be associated with Registry Permissions too.

Ways to Fix Windows Installer Service Could Not Be Accessed
After considering all the scenarios, we have detailed 4 workable solutions that can effectively get rid of Windows installer service could not be accessed error. Let’s have a look！

Solution 1: Uninstall the Older Version of the Program
Solution 2: Make Sure that the Installer Service is Running
Solution 3: Register Microsoft Installer Service Again
Solution 4: Install Windows Installer Again

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