If you have the Ultimate or Enterprise edition for Windows Vista or Windows 7, you can download additional language packs by using Windows Update. Once you turn on Windows Update, you can choose which languages you want to install (language packs don't update automatically). Here’s how to do it.
In the list of results, click Windows Update.
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.
To download language packs for Windows 7
Click the Start button , and then, in the search box, type Windows Update.In the list of results, click Windows Update.
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.