18. The computer-readable storage device of claim 16 , wherein the operations further comprise comparing a hash value determined from the feature vector to file identifiers in a memory, wherein the classification data is generated by the trained file classifier based on a determination that the hash value does not match one of the file identifiers.
19. The computer-readable storage device of claim 18 , wherein the operations further comprise generating the hash value based on the feature vector before comparing the hash value to the file identifiers in the memory.