Using Time Machine for your backups, however, changes everything.
If you aren't using Time Machine, you are still making regular backups (right? right?) of your hard drive. But depending on how often your regular backups were, your Trashed file might or might not be available for recovery. If you Trash a file newer than your most recent backup and immediately realize you made a huge mistake, you are out of luck.
Time Machine, however, is happily working in the background making backups for you every hour for the current day. It then keeps daily backups for a month. I'll bet you tons of money that that is alot more often than you would be making manual backups.
Now, if you Trash a file, as long as it is more than an hour old, you can just go to Time Machine and get it back.
But, aye, there's the rub. What if you wanted to get rid of that file forever? Time Machine still has a copy of it. And what about Secure Empty Trash? Yep, Time Machine will recover that file in the blink of an eye.
So what to do? The answer is not at all obvious, but here it is:
- Activate Time Machine.
- Locate the file that you deleted that you want gone forever and select it.
- Go to the gear button in the tool bar and select "Remove from Time Machine"
If you regularly need to use Secure Empty Trash, then Time Machine may not be the best backup option for you. Stick with regular backups to an external hard drive that you can physically secure.