Folder copy, source/destination contents do not match in Explorer

hello!

for some reason, after doing some successful folder copies (ie no errors) from my external USB drive to my RAID 1 NAS, the contents of some source folders and their respective destination folders do not match in windows explorer, ie file/folder count and size are different. other folder copies do not appear to have this issue, only a select few.

the USB drive is FAT32, the NAS is EXT3, though windows explorer sees it as NTFS.

for example, here's what i'm seeing in windows explorer when i right-click/properties on a source and destination folder..

- source folder
folders = 575
files = 75
size = 28.5 GB (this is not size on disk)

- destination folder
folders = 583
files = 80
size = 31.6 GB

if i hover the mouse pointer over the source folder, the tooltop shows 33.8 GB, which more closely matches the destination folder properties (tooltip for the destination folder also shows 33.8 GB).

if i look at the folder properties for the source folder under linux (parted magic live disc), the numbers are closer to what the destination shows in windows explorer, size is a couple GB higher under linux vs windows- not sure if linux serves as a good test.

my question, is what i'm seeing for the source folder properties in windows explorer a "misread", or is it possible that there was an issue with the copy process that i'm not seeing? the USB drive contains important data and i want to make sure i have an exact copy on the NAS before i wipe the USB drive to reuse it.

i've done the folder copy using a few other file managers (explorer++, xyplorer) but i get the same results.

thanks for your time!

Hi there. It's just the way Windows catalogues the files. It creates some hidden desktop.ini files and such. I wouldn't be concerned about it, however, real important files should be backed up in at least 2 places. Do you have another thumb or DVD you could copy to as well? How about OneDrive or other cloud storage?

HippsieGypsie said:

Hi there. It's just the way Windows catalogues the files. It creates some hidden desktop.ini files and such. I wouldn't be concerned about it, however, real important files should be backed up in at least 2 places. Do you have another thumb or DVD you could copy to as well? How about OneDrive or other cloud storage?

thanks for the response! i don't have another storage device at the moment, and the USB drive has 500 GB of data in total so DVDs and cloud storage probably wouldn't work.

if this is in fact just the way Windows catalogues files as you suggested, why would it only affect some folders but not others? would file types have a bearing on this? the difference in files/folders count and size between source and destination (in my opinion) seems a little too steep to be just hidden ini files etc- the size difference alone is 3 GB..

@Matt26

Sorry, but this got hidden in my 2nd subscription page and overlooked it.

I'm not that knowledgeable to know how File Explorer works. I searched the TechNet site and the web to no avail. I'm sure it's quite complicated. Each OS has its different version as explained in the article below. Better indexing for querying is probably a factor.

File Explorer - Wikipedia

How are you doing on this?

HippsieGypsie said:

@Matt26

Sorry, but this got hidden in my 2nd subscription page and overlooked it.

I'm not that knowledgeable to know how File Explorer works. I searched the TechNet site and the web to no avail. I'm sure it's quite complicated. Each OS has its different version as explained in the article below. Better indexing for querying is probably a factor.

File Explorer - Wikipedia

How are you doing on this?

i'm getting gradually baffled by this to be honest.. seems like a FAT32 issue based on my readings, more specifically maybe related to large files (like 4+ GB). as a test, i formatted a spare 60GB USB drive as FAT32, then copied one of the problematic source folders to this drive- my theory being that if FAT32 is the issue, the destination folder in this test should show the same "misread" of folder properties as the source (ie, show file, folder and size counts as lower than actual); unfortunately this didn't happen- the FAT32 test drive showed the folder properties accurately, so i'm at a loss.. i wonder if i were to plug the source USB drive into a computer with a FAT32 OS, would that make a difference? i just wish i could find a way to either get windows explorer to show the folder properties correctly, or find a third party alternative that can- i'd use linux, which appears to read the problematic source folders accurately, but linux (ubunutu anyways) doesn't give file and folder count details, just size- and only in GB, doesn't show byte count..

For backup and comparison between two folders I use the freeware FreeFileSync. It tells you whether there are differences between the two folders. It works also in a network environment.