Windows 7 Ultimate Sometimes Chinese Characters Show Up As Squares

hi, I have been having this problem for more than a year, my windows 7 ultimate is able to recognise and display chinese characters in the past, but very often, sometimes the chinese characters doesn't display properly, and after i restart the operating system, it shows up fine. is there any problem with my OS? majority of the time it shows the chinese characters properly, but often it messes up the chinese characters and displays squares.

no one has this problem?

because ultimate is supposed to display chinese characters without installing the language packs, and i'm not a chinese program user, so setting my language to chinese is a bit too much, it's just some of my songs have chinese titles. it happens randomly only, and after i restart my computer or go to the regional language settings, change to chinese, restart and change back to english, the problems goes away... for a while, before randomly appearing again.