MS Windows

MS WindowsMicrosoft Windows has been localized into many languages worldwide. Some of the Windows versions were introduced with the Multilingual User Interface Technology (MUI). Microsoft first introduced the Multilingual User Interface Technology for Windows 2000 Professional as "Windows 2000 Professional Multilanguage Version," which was later extended to the Windows 2000 Server family. This technology is now called Multilingual User Interface Pack, referred to as MUI.

Why should I need an English message?

When you know exactly the original English message then you can search for it on the Internet and find out an artical or some other resources regarding the message in a common computer language.

Sources:
msdn.microsoft.com
Other links:
Browsing MS Windows catalog