The "Change the display language " feature Jupiter Jones references will not
be the same as changing all the language in your OS any more than you can
get a magic wand to change your car make. It is limited. The only
substitute for complete language change is an English version or whatever
version, however there are some things you can do to enhance what is in
Windows for free.
The display language is the language that Windows uses in wizards, dialog
boxes, menus, Help and Support topics, and other items in the user
interface.
When you change the display language, the text in menus and dialog boxes for
some programs might not be in the language that you want. This happens
because the program might not support Unicode.
For more information about changing the text in menus and dialog boxes for
programs that do not support Unicode, see Change the system locale.
With additional language files, you can change the display language on your
computer so that you can view wizards, dialog boxes, menus, Help topics, and
other items in Windows in a different language.
There are two types of language files:
Windows Vista Multilingual User Interface Pack (MUI).‌ Windows Vista MUIs
provide a translated version of most of the user interface. MUIs require a
license to be used and are only available with Windows Vista Ultimate and
Windows Vista Enterprise.
Windows Vista Language Interface Pack (LIP).‌ Windows Vista LIPs provide a
translated version of the most widely used areas of the user interface. LIPs
are freely available for download on the Microsoft website, and most LIPs
can be installed and used on any edition of Windows Vista. Because not all
of the user interface is translated, LIPs require at least one parent
language. The parts of the user interface that are not translated into the
LIP language are displayed in the parent language. When you download a LIP,
you are given the parent language requirements for that language. The parent
language pack needs to be installed before the LIP can be installed.
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