OK…I’ve got this undeletable file and can’t figure out how to get rid of it…rebooting doesn’t help.
Running Big Sur and in /Users/Shared I’ve got a file named Install macOS Mojave so it’s been around through a couple of OS updates. Inside the package there’s a single file at Contents/SharedSupport/InstallESD.dmg. Get Info says system has R/W and wheel and everyone have R Only access…and I’m unable to change the access even when logged in as an admin user.
Moving the package to the trash requires admin credentials…but when I try to empty the trash I get “can’t be completed because the file is in use”.
Tried shift booting so nothing extraneous gets loaded and logging in as admin user…no luck.
Tried logging in as admin, launching terminal, and then su to root (I enabled the root user long ago) and then deleting it from terminal…no luck.
Doing ls -la in terminal as root shows
-rw-r–r-- 1 root wheel 5544818527 Dec 12 2020 InstallESD.dmg
So how do I get rid of this file…my guess is I need to chmod of some sort and/or then use some sort of rm command with the right magical incantation switches afterwards. I’m comfortable with slight to minimal user use of terminal but a command line geek I’m not…so I hope somebody smarter than me can point me to the obvious solution. Boot into single user mode maybe? Who knows.