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why does robocopy say this file is older?

Robocopy shows (I think I used /MIR and /L)

   2    M:\bk\laptopcopy\pics\
        Older              79248    regular-expressions-cheat-sheet-v2.png

None of the time stamps seem to reflect that though.

---- dir showing the modified time stamp
M:\>dir m:\bk\laptopcopy\pics
Tue 22 Jul 2008  05:01            79,248 regular-expressions-cheat-sheet-v2.png

>dir regular-expressions-cheat-sheet-v2.png
22/07/2008  05:01            79,248 regular-expressions-cheat-sheet-v2.png

---dir showing the creation time stamp----
>dir /t:c regular-expressions-cheat-sheet-v2.png
24/08/2008  16:04            79,248 regular-expressions-cheat-s

>dir /t:c regular-expressions-cheat-sheet-v2.png
24/08/2008  16:04            79,248 regular-expressions-cheat-s

--- dir showing the access time stamp    
>dir /t:a regular-expressions-cheat-sheet-v2.png
20/04/2013  11:23            79,248 regular-expressions-cheat-sh

>dir /t:a regular-expressions-cheat-sheet-v2.png
29/12/2010  14:31            79,248 regular-expressions-cheat-sh

Documentation says [1]

File        Exists In   Exists In        Source/Dest     Source/Dest   Source/Dest
Class       Source      Destination      File Times      File Sizes    Attributes
=========== =========== ================ =============== ============= ============
Lonely      Yes         No               n/a             n/a           n/a
Tweaked     Yes         Yes              Equal           Equal         Different
Same        Yes         Yes              Equal           Equal         Equal
Changed     Yes         Yes              Equal           Different     n/a
Newer       Yes         Yes              Source > Dest   n/a           n/a
Older       Yes         Yes              Source < Dest   n/a           n/a
Extra       No          Yes              n/a             n/a           n/a
Mismatched  Yes (file)  Yes (directory)  n/a             n/a           n/a

[1] What does robocopy mean by tweaked, lonely and extra?

Which mentions documentation and and

share|improve this question
The last set of time stamps seems to reflect older doesn't it? If M: is the Source and F: Destination. – N4TKD Apr 28 '13 at 0:46
@AlwaysLearning I don't think so. older is when source is older than dest. newer is when source is newer than dest. also I don't think it looks at access time(which that is), and, I think those access times are a case of Newer rather than Older. source>dest. See that table – barlop Apr 28 '13 at 7:15
Good point I move to SnycToy long ago, because of issues like these you may want to think about switching if you can. – N4TKD Apr 28 '13 at 12:27
@AlwaysLearning thanks i'll consider that. Currently I use beyond compare to check my copies sometimes. but I think 'beyond compare' might also do a copy, or syncing or sync related operations. I actually haven't ever used robocopy for my backups and have only just tried it now. Normally I use fastcopy but that is behaving in a similarly odd manner all of a sudden, which has never happened before. Though now I think about it, I did copy files to new hard drives 'cos I changed 2 hard drives in that computer. In which case I could delete the backup recreate it, and the problem won't recur. – barlop Apr 28 '13 at 13:52
@AlwaysLearning but I might dig a bit (or a lot if i'm nuts) just to figure out what is going on in more detail 'cos that often helps for the future. – barlop Apr 28 '13 at 13:55
up vote 4 down vote accepted

I had the same issue and came across the following:

Basically, this indicates that you can use the /FFT switch to Assume FAT File Times (2-second date/time granularity).

Using this now and I no longer get 100000 identical files overwritten.

share|improve this answer
i'll give that a try soon if I still have those paths/files, though in my case C:\ and F:\ are NTFS. Though the files were copied via (poss FAT) usb stick. anyhow, i'll try that soon. – barlop Oct 17 '14 at 21:41
The /FFT works - doesn't say one file is older/newer. Though both M:\ and F:\ are NTFS.. also I have the file elsewhere on F with all times other than access time the same, and with the other one robocopy doesn't require the /FFT for some reason. So, not only is it not the file system but it's not that one file comes from a usb and one doesn't. I don't at this stage know why it works or what's going on which is a bit disconcerting for if I was to use robocopy or another program with this issue. – barlop Oct 18 '14 at 0:33

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