Actually Gumby is more right then he thinks. You have to remember that Perms Remove will either remove an account or an index entry. Well "Everyone" is not a regular account.

If you change your approach to what Gumby has suggested, you will be able to remove the index entry for "Everyone" Just remember to add a few checks since if you simply say "remove (4)" it will remove what ever is found at index entry 4.