File was changed or forged

Been playing CF for quite some time now. I got a new computer and loaded up CF on the new box. It went through the patch procedure and when it trys to load up it states: 'File was changed or forged. Game will be shut down by force.' I have reinstalled 5 times with no success. I have done all the suggestions on the web such as clearing out my temp files and it still doesn't work. I have had a professional IT guy come look at this issue and he can't figure out why it's not working either. I need this fixed. I have paid $$ to you guys and I need some support here. Please advise.