You can add display languages by installing additional language files. When you install language files, 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 7 language packs. Windows 7 language packs provide a translated version of most of the user interface.
Language packs are available in Windows 7 Ultimate through Windows Update as optional updates. They aren't installed automatically. If you're using Windows 7 Enterprise, contact your system administrator for information about installing additional languages.
Language packs are available through Windows Update as optional updates. They aren't installed automatically.
Open Windows Update by clicking the Start button . In the search box, type Update, and then, in the list of results, click Windows Update.
In the left pane, click Check online for updates from Microsoft Update, and then wait while Windows looks for the latest updates for your computer.
If any updates are found, click Optional updates are available.
Under Windows 7 Language Packs, select only the language pack that you want (installing all of them might take up too much space on your drive).
Click OK, and then click Install updates.
If you're prompted for an administrator password or confirmation, type the password or provide confirmation. You might have to restart your computer.
If Windows doesn't find any updates when you click Check online for updates from Microsoft Update, wait a day, and then try again.
Windows 7 Language Interface Pack (LIP). Windows 7 LIPs provide a translated version of the most widely used areas of the user interface. LIPs are freely available to download. Because not all of the user interface is translated, LIPs require at least one parent language. The parts of the user interface that aren't translated into the LIP language are displayed in the parent language. When you download the LIP, you get the parent language requirements for that language. The parent language pack needs to be installed before the LIP can be installed. For more information, including a list of available languages, go to Download languages for Windows
on Windows online.
Language packs and LIPs will work only in a genuine copy of Windows 7. For more information, see What is genuine Windows?