How a bug in Dropbox permanently deleted my 8000 photos

Jan Čurn
9 min readJul 29, 2014

TL;DR: If you are using Dropbox as a sole backup of your files, think again. Without making a mistake, you might lose your files.

I started using Dropbox back in 2009 and have always loved the service. Over time, I kept moving more and more files to my Dropbox folder and eventually had to upgrade to the Pro plan to keep up with the space requirements. In particular, I moved there all of my photos in order to be able to view/share them on-line and also to have them backed up. In April of this year, a hard drive in my laptop was running low on space so I decided to use the Dropbox’s Selective Sync feature to unsync some large directories from the laptop. Because there was never any problem with the service and also because it’s already the year 2014, I thought it might be about time that one can trust a cloud-based storage service and use them as a sole backup of their files. Boy, I was wrong.

On 29th April 2014, I opened the Selective Sync dialog, unchecked directories called 2003, 2004, …, 2014 from the Photos folder (and few other directories) and clicked the ‘Update’ button. After that, the Dropbox client froze and didn't show any sign of life for a couple of minutes, so I decided to kill it and restart it again. These directories are large and they might be too big of a bite for Dropbox, I thought, and unsynced them one by one instead. Everything worked well, the directories disappeared from the local hard drive, but they were still available on Dropbox’s website. All good.

About two months later when I was preparing for a defence of my PhD thesis, I was looking for an old presentation but couldn't find it. The directory was there but it was empty. I would have never deleted these files, something must have gone wrong. I contacted Dropbox support which then broke the news to me: there was a delete event of 8343 files from 2014-04-29 at 14:57:30 GMT (UTC). Looking at the log record from this event, I realised most of the missing files were my photos! All the directories were still in place but many of them were empty, as if Dropbox randomly deleted some files and left some others intact. I was devastated. All those memories and the effort with collecting and organizing the photos…. gone.

From all this information it seems that Dropbox client first deletes files locally before it informs the server about the new selective sync settings. Consequently, if the client crashes or is killed before the server is contacted, the files remain deleted without any trace. After the client restarts again, it only sees there are some files missing and syncs this new state with the server. Unfortunately for me, Dropbox only keeps a copy of deleted files for 30 days (unless you pay $40/year for some Packrat feature) and I found out about this event after two months.

For me it’s most likely over, there is nothing I can do now, maybe try to get some photos back from my friends who went to same trips. Anyway, I decided to share this story publicly for three reasons:

  1. A bit of publicity might convince Dropbox to put some extra effort and maybe find a way to restore my files.
  2. To let other Dropbox users know about this issue so that this doesn't happen to them. Basically after doing any major changes in Dropbox settings, one should check the Events page on Dropbox website to make sure no files got deleted.
  3. Dropbox team can use information from this story to fix the problem. Here are few suggestions what can be done:
    a) Make the application of the selective sync settings transactional, either is succeeds completely or fails gracefully.
    b) Enable the Packrat feature by default for every paying customer, without any extra cost. Looking at the storage plan pricing for Google Drive, there surely is a space for you to do that. Or, at least, keep the delete history as long as the deleted files fit into user’s quota, it’s a space users already paid for.
    c) Use machine learning to detect a strange activity on user accounts and notify users by email if it happens. For example, most of my activity over the years consists of adding large number of new files and changing/deleting a small number files from time to time. A sudden deletion of 8343 files is surely a strange activity in this context.

Many thanks for reading and up-voting this story on Hacker News.

PS: At least I defended my PhD thesis even without that lost presentation, but the photos are gone nonetheless.
PPS: For the sake of completeness, I'm attaching a complete record of my communication with the Dropbox support, see below.

EDIT (on 2014-07-30): Many thanks for all the feedback. Yesterday night I got an email from Dropbox saying that they worked with their engineering team and were able to restore 1463 files. Also I received some credit for my future use of the service. Better than nothing.

Follow me on Twitter at @jancurn

Jan Curn, Jun 30 09:28 AM:
Hi,

I was looking for an folder with a presentation from the last year, just to discover the folder is empty and not even the option “show delete files” shows anything. I’m sure my files were there and I’d have never deleted them. I was wondering, is there a way to maybe look into some older backups (let’s say from August 2013) and recover those old files?

The folder is called: [REDACTED]

Your help would be greatly appreciated.

Kind regards,
Jan Curn

Marla, Jun 30 09:49 AM:
Hello Jan,

Thanks for contacting Dropbox Support!

Dropbox can only restore files for 30 days after they are deleted from your account. Unfortunately, if those files were deleted more than 30 days ago, I will not be able to recover them. I’m really sorry.

Please note that Dropbox Pro users can add our Packrat feature, which gives them the ability to restore deleted files or previous versions of files beyond the 30 day window. For more information on Packrat, visit the following link:

https://www.dropbox.com/help/113

Keep in mind that Packrat is not retroactive. If your files were deleted or changed over 30 days ago, upgrading to Packrat will not make them available again.

Please let me know if you have any further questions.

Regards,
Marla

Jan Curn, Jul 01 02:06 AM:
Dear Marla,

thank you for your feedback. I’m aware that deleted files are only kept for
30 days, unless you pay for that Packrat feature. However, this is a very
critical situation for me so I wanted to ask specifically, is there really
no hidden backup that might contain my files?

I don’t remember touching that folder for about one year, the only thing I
did was that I updated the “Selective sync” settings so that the files from
the folder were not downloaded locally and I remember Dropbox crashed in
that process. Maybe that deleted the files. This was in April 2014, so
maybe a backup from that month would be sufficient.

Frankly, this issue doesn’t give me much confidence in Dropbox anymore,
because now I can’t be sure that my other files that are selectively not
synced won’t get lost.

Kind regards,
Jan Curn

Marla, Jul 01 09:47 AM:
Hi Jan,

Thanks for your response. Unfortunately these files were deleted around 63 days ago and I cannot recover them.

According to our records it appears that these files were deleted by the device ‘macbook’ on 2014-04-29 at 14:57:30 GMT (UTC). The link to this deletion event is below:

https://www.dropbox.com/event_details/[REDACTED]

You can also see which user and computer deleted or changed a file by looking at the “previous version history” or the “Events” page on the web site:

https://www.dropbox.com/events

For more information, please visit the following help center article:

https://www.dropbox.com/help/11

There are a number of different reasons that a delete could happen, but the Dropbox desktop client does not have the ability to tell how or why files were deleted, only that they were deleted. Possible reasons for unexpected deletions include:

· a user dragging the files/folders out of the Dropbox folder (or a shared folder) instead of copying them;
· backup software installed on the computer which unmounts the hard disk;
· human error (i.e. an inadvertent delete keystroke).

Connectivity issues may delay the actual synchronization so that the event timestamp is listed at a time when no one was using the computer.

The files could also be missing due to the intentional deletion of files from a device that shouldn’t be connected to the account anymore. You may want to review your connected devices here:

https://www.dropbox.com/account/manage

From there, you can unlink any that no longer needs to be linked to the account.

The Dropbox folder is just a normal folder and the Dropbox software only responds to changes after they happen. Neither the Dropbox desktop client nor the Dropbox servers have the ability to delete your files on their own.

Even a Dropbox bug or glitch would be on the client and not the server. Please try installing the latest version of the client. It has the latest fixes in it and may resolve the issue you’re experiencing.

https://www.dropbox.com/install

You can find more information on file deletions in our Help Center:

https://www.dropbox.com/help/40

Please let me know if there is anything else I can do for you.

Best,
Marla

Jan Curn, Jul 01 01:19 PM:
OH MY GOD!

It is much worse than I thought, *in total 8345 files were deleted*, mainly
my photos a videos…. This is an absolute disaster, I don’t have any other
backup of these files, Dropbox was supposed to be the backup.
The device ‘macbook’ is my laptop and on 2014-04-29 I was making some free
space on the disk by unchecking several large directories with photos and
other files in the selective sync settings. I remember that Dropbox client
crashed the first time. After restarting it I decided to uncheck the large
directories one-by-one in order to make it simpler to process for the
client. Everything went well, the directories disappeared from my hard disk
but they were still available on Dropbox website, so I assumed everything
was fine. Only now I realised that many files
from apparently random directories are gone, while all the empty
directories are still there.

Clearly, this must have been caused by some bug in the Dropbox client, as
it started to delete files from the disk before it committed the changes to
the server. I assume I had the latest version of the client, as it updates
automatically.

Is there really no way to restore these files, maybe from some tape
backups? I’m aware this might require some effort from your side or maybe
some other people in your company, and I’d be really grateful for it.

Regards,
Jan Curn

Marla, Jul 02 09:14 AM:
Hi Jan,

I want to let you know that I’ve passed your request to members of our team who specialize in this kind of request. They’ll review it carefully and get back to you as soon as possible.

In the meantime, if there’s any additional information that you think would be helpful for us to know, please feel free to reply.

Thank you.

Best,
Marla

Jan Curn, Jul 09 03:48 AM:
Hi Marla,

I was wondering, was there any success with restoration of my files? Nobody
from Dropbox got back to me.

Regards,
Jan

Alisa — Dropbox Support, Jul 14 11:45 AM:
Hi Jan,

Thanks for getting in touch with Dropbox Support. Marla let me know that you were inquiring about recovering deleted files. Unfortunately, as she noted, since the files were deleted more than 30 days ago, we cannot recover them. I’m exceedingly sorry to hear about your lost files and for any inconvenience this may cause, but I hope this helps to clear things up for you a bit.

Best,
Alisa — Dropbox Support

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Jan Čurn

Founder and CEO of Apify — the web scraping and automation platform. Ph.D. in AI. Y Combinator Fellow. https://apify.com/jancurn