MSU File

What are MSU files and how to open them

Are you having problems opening a MSU file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your MSU files.

What is a MSU file?

A .MSU file is a Windows Update Package file.

Files containing the .msu file extension are update installer files used by the Windows operating system. Files with the .msu extension contain updates for files and applications.

There are four elements in 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.

Before Vista, Windows would use MSI files for system updates rather than MSU files.

How to open MSU files

Important: Different programs may use files with the MSU file extension for different purposes, so unless you are sure which format your MSU file is, you may need to try a few different programs.

While we have not verified the app ourselves yet, our users have suggested a single MSU opener which you will find listed below.

Last updated: December 21, 2023

Various apps that use files with this extension

These apps are known to open certain types of MSU files. Remember, different programs may use MSU files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Help us help others

File.org helps thousands of users every day, and we would love to hear from you if you have additional information about MSU file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.