Yes, there are many possiblites for that outcome. It could be that the hack is patched or detected. Maybe you opened the hack or injected it after crossfire was already opened. Maybe you didn't run as admin if you use Windows vista. Firstly you should try another injector, if that doesn't work then there's something wrong with what your doing or the hack is patached or detected. I can be of more assistance to you if you give me your system (os) and the hack you are trying to inject.
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