MSU files contain source code for initializing Windows Vista system updates, upgrades, fixes and patches. An .XML file describes the MSU file contents. A properties file is read by Wusa.exe. The Windo...
MSU files contain source code for initializing Windows Vista system updates, upgrades, fixes and patches. An .XML file describes the MSU file contents. A properties file is read by Wusa.exe. The Windows operating system previously used .MSI files for updates. You can manually extract the MSU file contents in the Windows command prompt by typing: expand -f:* “example.msu” output_directory. You can manually install the update package by typing: “example.msu” output_directory.
MSU files support updates on Windows Vista systems and later versions. An MSU archive contains: Metadata, A CAB file with update data, An XML file with MSU content, and properties data for Windows Update.
MSU files contain Windows updates for files and applications with: update metadata describing the update package, A CAB file(s) with the actual update data, An XML file with information on the MSU file contents.
The MSU file extension helps Windows Vista users install updates without needing to search individually in Windows Update. This allows installing all updates together instead of failing to update with too many files.