I have a FAT32 flash drive full of old archived emails, and their creation/modification date is important because it represents when the email was received. I'm trying to copy these over to another computer (Windows 7, with an NTFS filesystem). I copy the files over, and it changes all of the creation/modification dates to the current date/time. I've tried manually copying through folders, using robocopy, and using xcopy, and have the same issue regardless. One strange observation is that, after I do a copy and have the destination folder open, the creation/modification times seem to be correct at first, but slowly convert over to the current time (when I click on a file, it has the correct date/time, but after a second or two changes to update to the current time; very frustrating).
Does anyone know a foolproof way to do copy over these emails while preserving timestamps?
EDIT: I can confirm that when I simply (single-)click on the file, its modified date is updated. Is this happening because the old modified date is newer than the creation date?
Best Answer
One mechanism by which the last modification date will "mysteriously" change after a file is created/copied is Windows Explorer. Raymond Chen describes one thing that Explorer does to files after they are extracted from untrusted archives that updates their last modification timestamps. In general, any post-creation/copying modifications to files by Windows Explorer that update alternate data streams will result in this effect. Exactly what modifications can occur depends from what types these files are (You don't say.) and what Explorer extensions you have (You don't say.).