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I get a warning every time I try to copy any image (JPG, PNG, screenshot, camera photo, etc.) from my Dropbox to an external NAS (NetGear ReadyNAS NV+), stating:

Are you sure you want to copy this file without its properties?
The file myphoto.jpg has properties that can't be copied to the new location.

screenshot of warning dialog

Copying the image from Dropbox to another local folder does not produce this warning, but then later copying that image to my NAS results in the same warning.

Copying any other image from my local drive, that hasn't been in Dropbox, does not result in this warning, so it is something specific to Dropbox.

If I compare all the reported properties of the image (File > Properties > Details) then everything that is reported is OK and nothing is missing. The MD5 hash of both files is also the same.

This only seems to affect images. Text files and PDFs copy without warning.

I never got this warning with Windows XP.

  1. So, Dropbox is adding something to the image file properties, but what?

  2. This is a bit of an annoyance, as I'm always copying images from Dropbox to my NAS! So is there anyway to suppress, or preferably resolve, this warning?

Oliver Salzburg
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MrWhite
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2 Answers2

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In short, I think that you will lose some windows tags (or ntfs tags, whatever they call them) that are saved in the operating system or the disk. The comment above contains URLs that explain the possible information of those "properties".

The the image properties are not altered in any way.

Teracopy

Try using TeraCopy to suppress the messages: http://codesector.com/teracopy

A short description of teracopy from the website:

TeraCopy is designed to copy and move files at the maximum possible speed. It skips bad files during the copying process, and then displays them at the end of the transfer so that you can see which ones need attention. TeraCopy can automatically check the copied files for errors by calculating their CRC checksum values. It also provides a lot more information about the files being copied than its Windows counterpart. TeraCopy integrates with Windows Explorer's right-click menu and can be set as the default copy handler.

In this case, I believe that teracopy will not bother the user with meaningless "missing properties", ntfs/windows tags and whatnot, and will finish the job and mention any real problems/errors at the end of the transfer.

Total Commander

Total Commander: With dual-view or multi-tab view you can easily transfer files from one folder to some other folder. Total Commander is a powerful tool with many other features (regular expressions, renaming, select files by matching a specific rule etc.

There also exist free/open source alternatives

I'm not sure if any of them suppress the messages, but I suppose they do, since they're said to be more efficient in transferring files.

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I have found that files stored in the Dropbox storage synchronized folder in Windows have an alternate stream com.dropbox.attributes in the stored file, which contains information used by Dropbox storage system.

I used a small command line utility from SysInternals - Streams - to look at a simple jpg picture in my Dropbox storage. The utility displays alternate streams (think of alternate streams as stealth information stored alongside the original content when under NTFS). This is what I get:

c:\Temp>streams "C:\Store\Dropbox\Camera Uploads\2015-02-10 20.12.14.jpg"
Streams v1.56 - Enumerate alternate NTFS data streams

Copyright (C) 1999-2007 Mark Russinovich Sysinternals - www.sysinternals.com

C:\Store\Dropbox\Camera Uploads\2015-02-10 20.12.14.jpg:

:com.dropbox.attributes:$DATA        507

Hence it seems to me that ONLY Dropbox storage relevant information is lost when transferring the file to a nonNTFS store. In conclusion I would not have a problem transfering the files as such. Hope it helps. Cris