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mklink /J C:\Windows\Installer D:\WindowsInstaller Now we need to create a link from that location to the new path. Once move is complete original folder C:\Windows\Installer will be deleted. robocopy C:\Windows\Installer D:\WindowsInstaller /MOVE /E Use the same administrator command prompt we used for “ services.msc” to execute commands below. We have to perform these actions quickly to avoid Windows Update waking up and deciding to install something while we have things in flight. This would make sure that all existing and future patches are available to Windows Installer.
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If you’ve been running Windows for a while you may finder a lot of Windows patches in that folder.ĭo not delete files in this folder. Every file is important because it allows the Windows installer to create the right rollback plan and not leave any files lying around. These files will be used to apply future patches or rollback the application completely. MSP – a patch of an existing installationĮvery time a piece of software or system component is upgraded, MSI or MSP for that operation is cached in “ C:\Windows\Installer“. MSI – represents a brand new installation
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You may notice two types of files in that folder: Windows itself relies on Windows installer for upgrades and patching. Microsoft built a system to help with it and called it Windows Installer. If Installation fails to perform 5th action, it needs to undo the first 4 actions in the specific order. All of these actions need to be performed transactionally, meaning they either complete in their entirety or none of them at all.Patching installed software with minor or major versions.This could be the integration of a COM component for Windows Explorer, for example. Modify Windows Registry to add new components to the system.
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Copy files into a specific location on the hard drive, relative to the parent folder path.The interesting thing is that they all need to do about the same set of actions: Software packaging and distribution is a common challenge that software vendors face.
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