Text in japanese is displayed as squares on windows 7 (home premium, my version) on the whole system and iTunes.
Text is displayed correctly in Chrome.
How to fix this?
Japanese text ocationally shows up as squares in windows 7. Make sure "Hide fonts based on language settings" is unchecked.
Open start menu and type "fonts" in search box. Click on "Change fonts settings". Restart the system.
If that still shows squares between reboots, Create a file in your desktop with japanese text (shortcut to folder, etc) and it solves the problem.