Windows 10 Different size on disk for same file/similar drive

TRTrabz

New Member
Hello All,

I'm using 2 external HDD on my laptop under Windows 10.
Both are exactly the same: same brand, same model, same capacity, same format (NTFS). I use 1 for my daily use, the second one as backup which I synchronize frequently with the first one.
However I noticed a difference with some very small files (Java source files) for the used size on the disk.
On my first drive they take 0 byte when on the second they take 4096 bytes.
The "real" size of files is the same (704 bytes), only the space used on the disk differs.
I've tried to delete and copy/paste in both ways but the difference remains and I couldn't find any difference in the details/config of the drives.

Anyone would have an idea to explain this difference of behavior?
 
From an elevated command prompt run the command
fsutil fsinfo ntfsinfo C: replace C: with each drive letter. If they are in fact the same the information should mostly be identical
 
From an elevated command prompt run the command
fsutil fsinfo ntfsinfo C: replace C: with each drive letter. If they are in fact the same the information should mostly be identical

Thanks for your reply.
I've run the command you suggested and it seems both drives are identical:
37703

37704


Sorry my env is in French, but all info should be at standard position and easy to understand. If any doubt, please let me know and I'll translate if needed.
But still some files don't take the same size on the 2 disks.

BTW, but might actually be important, both drives are encrypted with VeraCrypt but same algorythm (AES+TwoFish+Serpent) and same hash (Whirlpool).

Any idea?
 
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Encryption won't matter that only applies to data at rest, not data in use. Do you have any compression enabled on the disks?
 
Encryption won't matter that only applies to data at rest, not data in use. Do you have any compression enabled on the disks?

Nothing that I've set up explicitly. Might have some default configuration on one of the disks but then I don't get why it happened to only one.
How could I check that?
 
It's possible the first file is a symbolic link to the second file since it's the same data.

If the file is in D:\Somefolder

In a command prompt you can type dir /AL D:\somefolder
 
Weird result:

dir /AL D:\MyFolder
Volume in drive D has no label.
Volume Serial Number is 4930-EF68

Directory of D:\MyFolder

File Not Found


And the drive does have a label.
 
There probably just are no symlinks at least user visible ones. I'm still inclined to say there may be links that are only in kernel mode and not visible.

You could try moving the non-zero sized file somewhere else and see if the other one shows a size afterward.
 
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