1. A method of generating a white list, said method comprising: scanning a computer file on a computer on a first day using a first virus pattern and determining that said computer file is malware free; scanning said computer file on a second day using a second virus pattern and determining that said computer file is malware free; determining whether a minimum time has elapsed between said first day and said second day; determining whether said computer file has been modified between said scanning on said first day and said scanning on said second day; and adding said computer file to said white list by changing a single binary digit in a white list data structure when it is determined that said minimum time has elapsed and when it is determined that said computer file has not been modified between said scannings.