The toughest files to delete from your Mac's Trash are those on an external drive, but following the steps below you should find discarding these from your computer very easy!
File Deletion on the Mac
The standard process of discarding trash on a Mac is pretty straightforward. All you need to do is drag the file or folder concerned to the Trash and it’s pretty much “job done"!
You would also use the same method if you wanted to uninstall software from your Mac, or if you have an external drive connected that you are about to disconnect. This is a fast, efficient means of disconnecting drives and discarding data, and one which users find easy to use. Emptying the trash is also easy, and can be used to save yourself some space on your computer.
However, it doesn’t always work as intended. Most particularly, you might have an external drive attached to your Mac, from which you are attempting to empty trash. Thanks to differences between the file structure of the external device and your Mac, you will may find that you run into trouble emptying the trash.
How Emptying the Trash Should Work
As we’ve already seen, using the trash can to discard objects such as old data, unneeded applications and external devices that you wish to disconnect is pretty straightforward.
But what happens when you empty the trash?
Basically, the contents are completely discarded, deleted permanently from your Mac. This action is performed by right-clicking the trashcan icon and selecting Empty Trash (at which point a confirmation notice is displayed) or by clicking the Dock icon to open the Trash folder and clicking the Empty button in the top right-hand corner.
The same process should work on all discarded items, although folders that existed on an external hard disk drive that have been sent to Trash may cause you problems, probably due to a permissions-related error.
Clearly this is a bit of a problem, but there are various steps that you can take both in the Mac OS X user interface and elsewhere to resolve this.
Forcing the Trash to Empty
If the standard Empty command doesn’t have the intended outcome and your trash items remain, open the Trash folder in the Finder and the use the Finder menu to invoke the Secure Empty Trash… command, which will need confirming in a second window.
Secure Empty Trash applies a complete deletion of the items and they will be rendered non-recoverable after performing this task. As such, use the command with care.
Failure to discard the item here will result in you having to think outside of the box. Basically, while there might be some ground to be gained by using the Terminal window and interrogating the trash can via UNIX command line the method isn’t reliable for this task.
Instead, another method is required. But before you do this, restart both your Mac and the external storage device, and once restarted check the Trash for your stubborn item - it might have been removed during the reboot!
Using Linux or Windows to Discard Mac Trash
Remember that we have stumbled upon this failure to delete because of data stored on an external drive that has been sent to the Trash.
When this data is added to the Trash, it doesn’t actually get moved to your Mac from the external drive, but instead to a folder called .Trashes, which is intended to synchronize with your main Trash folder.
In these situations where the data will not delete, something permissions-related is preventing the deletion from taking place, and the most efficient fix you will find is to disconnect the external device (remembering to drag it to the Trash first) and then connecting to a Windows or Linux computer. Here, use the native file system manager to delete .Trashes.
A few moments later, the data will be deleted, and you can check this by reconnecting the external drive to your Mac.
MacRumours Forum, http://forums.macrumors.com/showthread.php?t=597215
Screenshot by author.