1. A computer program product for controlling a computer to detect malware, said computer program product comprising: detecting logic operable to detect a file access request to a computer file by a requesting computer; file access clearance request generating logic operable to generate a file access clearance request including data identifying said computer file; file access clearance request transmitting logic operable to transmit said file access clearance request from said requesting computer to an assessment computer responsible for assessment of whether said computer file contains malware; file access clearance response receiving logic operable to receive at said requesting computer a file access clearance response from said assessment computer; and file access permitting logic operable if said file access clearance response indicates said computer file does not contain malware, to permit said file access request by said requesting computer.