Windows Language Pack

If you want to set the newly installed language pack as your default language, you need to follow two more steps.

Windows 8 Language Pack X64

Step 4: Once Windows completes the installation of the language pack, in the Language Control Panel, move up the language pack until the language is at the top of the list. For instance, you just installed Arabic language pack and want to set it your primary language, you need to move Arabic language pack to the top of the list.

Step 5: Sign out and sign back in to set the new language pack as your default one.

Please note that you need to install a separate language pack for Microsoft Office, and Windows language pack doesn’t help you translate the UI of third-party programs.