Opening MSU files

Did your computer fail to open a MSU file? We explain what MSU files are and recommend software that we know can open or convert your MSU files.

What is a MSU file?

Files that contain the .msu file extension are update installer files that are used by the Windows Vista operating system. Prior to Vista, Windows would use MSI files for system updates rather than MSU files.

Files with the .msu extension contain updates for files and applications. There are four elements contained within each MSU file including the update metadata, a CAB file (or multiple CAB files), an XML file, and a properties file.

The metadata portion of the MSU file describes the update package. The CAB file (or files) contains the actual update data. The XML file contains the information describing the contents of the MSU file.

The properties file is the portion of the MSU file that is read by the Wusa.exe application. The Windows Update utility uses this information to run the update on the user's computer.

Software that will open, convert or fix MSU files

Try a universal file viewer

In addition to the products listed above, I would suggest that you try a universal file viewer like Free File Viewer. It can open over 200 different types of files - and very likely yours too! Download Free File Viewer.

By Prof. Jones (The File Expert)

Chief Content Editor and File Expert

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