Mavericks: User no longer owner of Home folder and content

Question

One of the Users (called: The_Problematic_User) of a Mavericks installed MacBook Pro is no longer owner of the Home folder and content. Here's what we've tried to no avail:

• restart computer and log in recovery mode (Command-r) and;
  • repair disk permissions,
  • repair disk,
  • with resetpassword (command line),
  • reset Home Folder Permissions and ACLs,
  • reset password,
• restart computer and log in single user mode (Command-s which is root access) and;
  • Strip ACLs on all account items with: chmod -RN /Users/username
  • response: chmod: Failed to clear ACL on file ...
  • Try to regain ownership of files and folders with: chown -R username:staff /Users/username
  • response: chown: username: illegal user name (where username was the user name of the user, obviously)
  • Try to assign ownership of files to root with: chown -R root:staff /Users/username
  • response: chown: /Users/username/*: Read-only file system (where * represents all the files and folders in the directory)

Another thing: when I ls -l /Users here is what I get:

• drwxrwxrwt 6 root wheel 204 Feb 24 10:53 Shared
• drwxr-xr-x+ 12 501 staff 408 Mar 21 17:16 A_user (with admin privileges)
• drwxr-xr-x@ 47 502 staff 1598 Mar 15 12:03 The_Problematic_User
• drwxr-xr-x+ 24 505 staff 816 Jan 10 15:11 Another_user

What is the @ doing instead of the + in the permissions of The_Problematic_User?

For info: The_Problematic_User does NOT have admin privileges

Answer 1

An erroneous extended attribute has been applied to this directory somehow, but it can only be removed using the xattr Terminal command. You should take a look at a brief explanation here. A more detailed question and answer can be found at this StackOverflow page.