Can't empty certain files from trash (more precisely: old folders from Dropbox)

[Beliblis]

Hi,

I've got an old Dropbox folder+subfolders (no files) in my Trash which I can't delete. Every time I empty my trash, I need to skip these files, which is fairly annoying.
"The operation can't be completet because the item "WORK FILES" is in use.
Like to have things clean

The folder is from an external hard-drive, so obviously only shows up inside the trash when that hard-drive is connected. Tried everything: right-click the bottom-most nested folder and "Delete immediately..." deletes the folder. But 1s later the same folder re-appears.
Terminal command "lsof" shows the file is not in use.
(Dropbox is not running, and I killed all Dropbox background processes inside Activity Monitor).

The actual file location is : /Volumes/EXTERNAL-HD/.Trashes/503/Dropbox

That "503" in the path is a bit weird, though, isn't it?

Can anyone help, please?

 

[Brian33]

The 503 looks like a User ID number. I might be a little bit off, but basically Unix-style OSes (like macOS) associate a User ID (like 501) with a User Name (or account name, like "brian"), also not to be confused with a Full Name (like "Brian J. Jones"). macOS allocates User IDs starting at 501, and incrementing from there for each additional user account that you add.

Is your User account 503? If not that might be the problem. You can find out your account's numeric User ID by running this command in Terminal.app:

id -u

The filesystem remembers the "owner" of a file by recording the User ID with the file's metadata, not the User Name. Also, different Macs can have the same User Name, but assigned with different numeric User IDs. Thus a file written to an external drive could be owned by User Name "brian" on one Mac might not be owned by user "brian" on another Mac (and thus inaccessible).