Must Know tip for removing files from external hard drive!

[wolvestech]

(I'm new to the forum so if this isn't where this is suppose to be posted just let me know and i'll change it). Anyway, not sure if this is known or has been posted before, but just wanted to share this tip that everyone with an external hard drive should know.
SHORT VERSION: If you are deleting any file from an external hard drive, clear the trash WHILE the drive is still plugged in! If you clear the trash after the drive is unplugged then you didn't actually delete the files, and next time you plug the drive in to that computer your files will reappear in the trash can.
I have a 2TB external hard drive that I use for bringing work files home to work on occasionally and also, (when I am not using it for work) I let my family use it for school/whatever else. The other day I plugged it into my family's macbook to do some excel work, and I also deleted some old work files that I didn't need anymore. After I unplugged my drive I cleared the trash and then once I got to work I transferred my work stuff back to my work computer so my family could use the drive again. What I noticed is that if you delete something off of the hard drive, it will disappear from the trash once you unplug the hard drive, and you can't clear it until you plug the drive back in. So when I was letting family use the drive I noticed that all my work files that I previously thought I deleted were just sitting in the trash and could be viewed/restored.

 

[Tech198]

actually, its impossible to clear the trash of external drives, or external usb devices period when its unplugged

Each drive, including the internal one, has its own .Trash folder.. (reveal hidden files to show this)

 

[idmean]

That’s the macOS behaviour since I can remember...

 

[rudo.ba]

Did you really think that a deleted file from an external drive moves to an internal drive trash? Each mac-formatted disk has its own trash. Ever since Mac OS (before OS X / macOS).

 

[ApfelKuchen]

Folders are human-friendly metaphors that give users the illusion that their storage is neatly organized. While storage space is most definitely organized, it's organized in a way that maximizes utilization of storage space and minimizes read/write activity, not one that would necessarily be easy for a human to navigate. The File Manager app interprets the contents of the file directory system in a way that's easy for us to understand.

Folders are not physical locations on a drive - they are cross-references within the directory system. Files are not contiguous units, they're broken into small blocks of data that can be scattered about the drive - one block here, one block there... maybe the blocks occupy contiguous space on the drive, maybe they're scattered about the disk like so many autumn leaves.

If a file is moved from one folder to another, the actual file blocks don't move at all - only the directory listings get updated. If a file is "moved" to trash, the file's directory listing simply gets marked "Trashed." When the trash is emptied, the directory listings are removed, but the data blocks remain until they're over-written by new data.

 

[Unami]

well, no ****...

i got some additional news, that might shock you. when you delete a file, and empty out the trash, it's still not gone. the operating system just marks the space the file occupies as "empty" and will overwrite it only as soon as it needs to, which might be quite a long time. before that, it's relatively trivial to restore those deleted files again.

that's the reason why you have a "security" option in disk utility, that overwrites your data with random bits up to 7 times to make your data virtually unrecoverable.

 

[idmean]

well, no ****...

i got some additional news, that might shock you. when you delete a file, and empty out the trash, it's still not gone. the operating system just marks the space the file occupies as "empty" and will overwrite it only as soon as it needs to, which might be quite a long time. before that, it's relatively trivial to restore those deleted files again.

that's the reason why you have a "security" option in disk utility, that overwrites your data with random bits up to 7 times to make your data virtually unrecoverable.

Note that if you delete something on an SSD, though, it’s pretty much gone forever.

 

[MacGizmo]

This is the way it works on all computers, regardless of operating system. How can it delete a file on a drive that isn't plugged-in?

Now if you want to delete a file immediately, without even using the Trash, select the file and hit Command + Option + Delete.