Opening MSU files

Have a problem opening a .MSU file? We collect information about file formats and can explain what MSU files are. Additionally we recommend software suitable for opening or converting such files.

What is the .MSU file type?

The .msu filename extension denotes the Windows Update Standalone Package (.msu) file type used in the commercial Windows operating systems from Microsoft Corp. While Microsoft delivers most of their software updates and hotfixes online through the Windows Update Center, standalone update packages (.msu) are also made available.

The .msu file represents a single Windows Update package intended for offline installation (e.g., "Windows8.1-KB2937592-x64.msu"). It uses the Microsoft Cabinet archive format to package one or several CAB files, an update control XML file, and Windows Update metadata. In Windows Vista and later, the .msu file type is pre-associated with the Windows Update Standalone Installer (WUSA, "%SystemRoot%\System32\wusa.exe"), so that any offline update can be installed by double-clicking its .msu file. WUSA checks the package for applicability and attempts to install it, if all checks are successful and prerequisites are met.

A batch-file or PowerShell script can be written to automate installation of MSU updates. Besides, with a suitable archiver, any .msu package can be directly opened as a CAB archive.

Software to open or convert MSU files

You can open MSU files with the following programs: 

Popular formats