Dropbox engineers have fixed what appears to be a very ancient bug that during the past two weeks has resurfaced previously deleted folders for several Dropbox users.

According to multiple support threads started in the last three weeks and merged into one issue here, users had complained about old folders that they deleted years ago, magically reappearing on their devices.

Files as old as 2009 reappeared in Dropbox accounts

In some of these complaints users reported seeing folders they deleted in 2009 reappear on their devices overnight.

"I'm having this same problem – several different folders of old files from 2009–2011, deleted years ago but suddenly reappearing overnight. And I definitely haven't connected to an old computer, either," one user said.

"I deleted these files over 6 years ago," another said. "The devices I had those files on are long gone, and trashed."

One user that didn't receive an answer from Dropbox support in a timely manner went as far as changing his account password and disconnecting all sessions, thinking his account was compromised.

Bleeping Computer also observed the same issue last week, when a folder removed in 2010 resynced to your reporter's account.

Dropbox admits to keeping files around for years

On Thursday last week, a Dropbox representative finally acknowledged the problem on Dropbox behalf and proceeded to detail the problem and announce a fix.

A bug was preventing some files and folders from being fully deleted off of our servers, even after users had deleted them from their Dropbox accounts. While fixing the bug, we inadvertently restored the impacted files and folders to those users’ accounts. This was our mistake; it wasn’t due to a third party and you weren’t hacked.

Wait, what?!? Dropbox was keeping your years-old deleted files around?

Typically, we permanently remove files and folders from our servers within 60 days of a user deleting them. However, the deleted files and folders impacted by this bug had metadata inconsistencies. So we quarantined and excluded them from the permanent deletion process until the metadata could be fixed. During this time no one had access to your files or folders and none of your other files were affected.

The Dropbox employee went on to reveal the company had implemented a fix, and most of these old files had been desynced and removed from affected accounts.

By this point, if you're not angry about Dropbox keeping your junk files around for years, you're probably baffled that it took them around eight years to fix a bug.