I Need Help With this Problem " The File is Changed ]0 crossfire.exe "

2 days ago i started crossfire normally...but while HGWC Process...a Message appeared with " The File is Changed ]0 crossfire.exe ..i dunno what to do with this problem ...
And i deleted the game a tried to download it from z8 but when i click at crossfiredownloader a message appeared also with alot of words but means that i have a Pando Booster problems..what is pando booster and what should i do ?