file not open to newer version of coreldraw installed

hi, can anyone here help me solved my problem, coz right now i installed coreldraw suite 11 and when i open all my previous save works using lower version coreldraw X4 it only appears white page, it wont open for me to continue working my job. is there any way to open it, for im tired of uninstalling/installed the lower version again and i want to try using the higher version. hope someone can help me solve my problem here. thanks