My computer does not allow me to type Chinese, it only input English letters

NJStar needs to intercept, or hook the keyboard in order to input Chinese via pinyin or other IME, but it can't intercept keyboard on your computer. There are two posibilities:

  1. Your PC has been infected with a virus which have already hooked the keyboard so NJStar is unable to hook.

    To verify it, please download NJStar on another computer (for example, your friend's computer or office computer) and install the latest NJStar Communicator to test. If other computers work OK with NJStar Communicator, you definitely need to have your computer scanned thoroughly for viruses.
     

  2. The anti-virus or anti-spyware program (such as SpywareDoctor) on your PC prevents NJStar from hooking the keyboard.

    This is a good measure against key logger type spyware, but NJStar does need to hook the keyboard in order to work. You must tell the anti-spyware program to allow trusted NJStar to hook the keyboard.