Dropbox says it was responsible for an attempted bug fix that instead caused old, deleted data to reappear on the site.

A worker said last week that while trying to address a bug that had caused some old files to reappear, someone at Dropbox instead set a huge archive of old information to visible, causing even more deleted content to reappear.

"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," Dropbox employee Ross S said on the company's support forum.

"So we quarantined and excluded them from the permanent deletion process until the metadata could be fixed."

Dropbox noted that the data was only visible to the accounts of the users, and at no time did any third party have access to the exposed files.

This after users had been complaining that old files, some more than a half-decade in the past, had been showing up.

"Several different folders of old files from 2009–2011, deleted years ago but suddenly reappearing overnight," wrote one user. "And I definitely haven't connected to an old computer, either."

"Two days ago, a folder mysteriously appeared in my dropbox folder. Some time later a subfolder was added and a word file was added," noted another. "The folder and the files therein were mine but had been deleted years ago."

While Dropbox said it had fixed the bug causing the issue, the restored files were left visible (users could manually remove them) for a few days. Dropbox on Sunday began to automatically remove the files.

Some users, however, are still reporting seeing their old files reappear, suggesting Dropbox has not yet fully cleaned up the mess. ®