wrong CRC?

so I double click crossfire and it opens no problems. I click start and the autopatch comes up and starts working then a box will come up wrong crc has been detected its auto patch v.5 if it helps and as far as im aware there arnt any other posts on this and if there are just link them to me. its not my antivirus software (norton) cose I have tried it with it disabled and it still doesnt work.
please help
thanks