Next time, Please post in the correct section;
CrossFire Help - MPGH - MultiPlayer Game Hacking
To Answer your question;
Try Completely uninstalling Crossfire, And Re-Installing, Also Restart your computer. A File Might have been Modified Or Mis-loaded/Patched.
https://crossfire.z8games.com/downloadS2.aspx
If you continue to get the error, Please Post.