Following [Aditya Soni's][2] great advice [here][1], I downloaded timestamps from Microsoft and created this python dictionary that maps Microsoft's AvSigVersion (str) to a timestamp (datetime.datetime). Use this to add timestamps to the data in Kaggle's Microsoft malware detection [competition][3]. There are 9622 entries in this dictionary. One for each unique valid AvSigVersion. Note that some computers have AvSigVersion = '0.0.0.0' and this key is not in the dictionary. AvSigVersion is updated approximately every 2 hours (in 2018). These are the malware definitions. Antivirus software cannot work without them, so 95% of users continually update them making this a trustworthy timestamp for each dataset observation. These timestamps were downloaded from https://www.microsoft.com/en-us/wdsi/definitions/antimalware-definition-release-notes For a dictionary of timestamps for Census_OSVersion which gives the time that the OS was last updated, go here: https://www.kaggle.com/cdeotte/malware-timestamps-2 [1]:https://www.kaggle.com/c/microsoft-malware-prediction/discussion/76384#449402 [2]:https://www.kaggle.com/adityaecdrid] [3]:https://www.kaggle.com/c/microsoft-malware-prediction