Advanced Folder Exclusions Recommendation in Emsisoft Anti-Malware Home Posted December 14, 2016 · Report reply On 12/14/2016 at 4:26 AM, GT500 said: Unfortunately hash generation takes time, and for an entire directory it could easily take a ridiculous amount of time. My best guess is that it would lead to system freezing as new files were saved in a folder, unless the feature only applied to the on-demand scanner. Using file size and last modified date would significantly reduce the amount of processing that would be needed to pull such a thing off, but obviously wouldn't be infallible. Granted, neither are hashes. Yes, but I didn't mean make a hash of every file and save them; instead make a directory listing (a small text file in essence) and save the hash of that.