I'm unable to delete a file within File Explorer's navigation area.
I'm unable to delete a file within File Explorer's navigation area.
I also attempted to remove Dropbox and deleted it, but it doesn't appear to be located.
You've checked nearly everything, but it appears to be placed in a fixed part of the system. It seems someone might have created a registry entry that didn't get cleaned up properly after uninstallation. You could look up a tutorial on adding custom folders to the Explorer sidebar for more guidance.