The way the Trash works is pretty straight-forward for your internal drive. But how about files on external or removable drives? Any file you put in the trash remains on that drive, but appears as a aggregated list when you view the Trash folder. You can only see files in the Trash on the same computer and user that threw them away.
Comments: 18 Responses to “How Mac Trash Handles External Drive Files”
ARC
6 years ago
Awesome topic. I always wondered why Mac behaves this way, makes sense now. Especially the part about security and trash from one user not being visible to another.
Fred Balfour
6 years ago
As Gary sez, a “trashed” file on external device stays until owner deletes it. So, User#1 trashes 5mbyte file on 10mbyte thumb drive, & dismounts. User#2 mounts drive, sees empty 10Mb drive with 5Mb free. User#2 pays Patreon for MacMost & knows most likely scenario is another user’s file(s) are there. User#2 works at a forensics firm & knows that she can read “trashed” invisible file if she wants to. So beware. Only way for user#2 to get rid of trashed file is to reformat drive, correct?
Fred: Yes, reformatting the drive will get rid of everything. When making this tutorial, I was thinking of "users" as accounts on your Macs. Naturally, if you plan to give a USB drive to another person and you don't trust them, then you should make sure that you empty the trash/reformat the drive, etc.
Bob Hunter
6 years ago
This also explains how a thumb drive seems to hold less and less over time if you never empty trash while the thumb drive is plugged in.
Patrick McEnroe
6 years ago
Hi Gary, what if I give the thumb drive to a Windows user? Will my trash still be secure? Thanks, Pat.
Patrick: If your drive is formatted for macOS, then a Windows user won't be able to do anything with it. If it is formatted for Windows (FAT32, etc), then I'm not sure if there is a trash at all -- files may just be deleted. You'd have to try that and see.
Louise Kienast
6 years ago
I can't remove an InProgress file from trash. It says "The operation can't be completed because the item "folders" is in use.
Louise: Try quitting all applications until you quit the one that is using this item. If you quit everything and you still can't empty the trash, try restarting.
Louise Kienast
6 years ago
The file is from my external hard drive used with Time Machine. I have learned that you can't delete these files from the trash since they are not actually part of the computer trash but the hard drive trash.
Louise: Hard to say what you should do without knowing what type of file it is, what created it, and why it won't delete. Did you try simply getting Info on that file and changing its permissions? Also, look at: https://support.apple.com/en-us/HT201583
Louise Kienast
6 years ago
Thanks Gary,
I will try later today and see if it works. The file is a package file. (2018-09-23-174423.inProgress). It is located in My Time Machine Hard Drive .Trashes Trash. Size zero bytes. It was created by a failed backup in Time Machine. I have not backed up in six months and this behavior has happened before. I was able to delete the file I think when it happened before. (the empty rectangles above are supposed to be right facing carets).
Louise: You haven't backed up in 6 months! That's a far far more serious issue than a file stuck in the trash. I would think about clearing that drive up (or getting a new one) and starting a new backup immediately. Then I would let it back up normally (hourly) after that. It is a very bad idea to go without a backup.
Louise Kienast
6 years ago
OK, I'm going out to get one now. I do back up important files, but I don't use Time Machine. I just move individual files into folders so they look like my computer files. That means I am not copying the applications nor most of the unimportant files, just the ones that are important. I do that often but not hourly. Thanks for the advice.
Louise Kienast
6 years ago
Success! Thanks to a thunderstorm I decided to try once again to back up. Just finished. I'll keep it up. Now I just have that silly file in the trash I can't delete. I saw that some have used the Terminal to remove the file from the hard drive. Is that a good idea? I don't like to do something just because it is mentioned on YouTube.
Louise: Try the method in that link I included above.
Louise Kienast
6 years ago
I tried each suggestion on the link you sent. I still can't remove the file that way. I found this topic: how to get rid of time machine backups in trash, with a link to a YouTube video using Terminal. I still don't know if this is a good method. The external hard drive is fine and I can use TM even with that file in the trash, so maybe it doesn't matter. It only shows up when I connect the external hard drive anyway.
Louise: I would only use Terminal for things like this if you feel comfortable. I'm surprised running disk First Aid on the drive didn't work.
Louise Kienast
6 years ago
WOW! I have been backing up with TM and today I installed Mojave. I tried once more to delete that file and guess what? It's GONE! I think sometimes you have to just wait. Perhaps the update fixed the problem.
Awesome topic. I always wondered why Mac behaves this way, makes sense now. Especially the part about security and trash from one user not being visible to another.
As Gary sez, a “trashed” file on external device stays until owner deletes it. So, User#1 trashes 5mbyte file on 10mbyte thumb drive, & dismounts. User#2 mounts drive, sees empty 10Mb drive with 5Mb free. User#2 pays Patreon for MacMost & knows most likely scenario is another user’s file(s) are there. User#2 works at a forensics firm & knows that she can read “trashed” invisible file if she wants to. So beware. Only way for user#2 to get rid of trashed file is to reformat drive, correct?
Fred: Yes, reformatting the drive will get rid of everything. When making this tutorial, I was thinking of "users" as accounts on your Macs. Naturally, if you plan to give a USB drive to another person and you don't trust them, then you should make sure that you empty the trash/reformat the drive, etc.
This also explains how a thumb drive seems to hold less and less over time if you never empty trash while the thumb drive is plugged in.
Hi Gary, what if I give the thumb drive to a Windows user? Will my trash still be secure? Thanks, Pat.
Patrick: If your drive is formatted for macOS, then a Windows user won't be able to do anything with it. If it is formatted for Windows (FAT32, etc), then I'm not sure if there is a trash at all -- files may just be deleted. You'd have to try that and see.
I can't remove an InProgress file from trash. It says "The operation can't be completed because the item "folders" is in use.
Louise: Try quitting all applications until you quit the one that is using this item. If you quit everything and you still can't empty the trash, try restarting.
The file is from my external hard drive used with Time Machine. I have learned that you can't delete these files from the trash since they are not actually part of the computer trash but the hard drive trash.
Louise: Hard to say what you should do without knowing what type of file it is, what created it, and why it won't delete. Did you try simply getting Info on that file and changing its permissions? Also, look at: https://support.apple.com/en-us/HT201583
Thanks Gary,
I will try later today and see if it works. The file is a package file. (2018-09-23-174423.inProgress). It is located in My Time Machine Hard Drive .Trashes Trash. Size zero bytes. It was created by a failed backup in Time Machine. I have not backed up in six months and this behavior has happened before. I was able to delete the file I think when it happened before. (the empty rectangles above are supposed to be right facing carets).
Louise: You haven't backed up in 6 months! That's a far far more serious issue than a file stuck in the trash. I would think about clearing that drive up (or getting a new one) and starting a new backup immediately. Then I would let it back up normally (hourly) after that. It is a very bad idea to go without a backup.
OK, I'm going out to get one now. I do back up important files, but I don't use Time Machine. I just move individual files into folders so they look like my computer files. That means I am not copying the applications nor most of the unimportant files, just the ones that are important. I do that often but not hourly. Thanks for the advice.
Success! Thanks to a thunderstorm I decided to try once again to back up. Just finished. I'll keep it up. Now I just have that silly file in the trash I can't delete. I saw that some have used the Terminal to remove the file from the hard drive. Is that a good idea? I don't like to do something just because it is mentioned on YouTube.
Louise: Try the method in that link I included above.
I tried each suggestion on the link you sent. I still can't remove the file that way. I found this topic: how to get rid of time machine backups in trash, with a link to a YouTube video using Terminal. I still don't know if this is a good method. The external hard drive is fine and I can use TM even with that file in the trash, so maybe it doesn't matter. It only shows up when I connect the external hard drive anyway.
Louise: I would only use Terminal for things like this if you feel comfortable. I'm surprised running disk First Aid on the drive didn't work.
WOW! I have been backing up with TM and today I installed Mojave. I tried once more to delete that file and guess what? It's GONE! I think sometimes you have to just wait. Perhaps the update fixed the problem.