Install Language Pack for WIndows 7 Pro

Recently I have to install a Windows 7 for my friend's laptop, and the display language should be Chinese. I download the Windows 7 Pro from ELMS for ASU, and installed it smoothly. Windows finally learns something from Linux, so now all the drivers are downloaded and installed automatically via the internet during installation.

Then, changing the language from Eng to something else requires a little hacking. I downloaded the language pack DVD from ELMS also, and copy the lp.cab under (DVD)\zh-cn\ to E:\lp.cab

Then, I did the following:
-run command prompt as administrator
-type dism /online /add-package /packagepath:E:lp.cab
-in regedit del key \HKLM\SYSTEM\CurrentControlSet\Control\MUI UILanguage\eu-us

Then, restart and everything works.