If you're referring to the little padlock attached to the folder, it's always been a security issue for me related to users being allowed access to the folder.
I clear my problems on the "Security" tab under folder "Properties". I have three users on all our computers: me, wife and a generic user. When all three users are afforded rights, the padlock goes away. Sometimes for reasons I cannot figure out (and gave up on trying to) Windows adds users with cryptic names on the "Security" tab only. Those I had to delete. If a user is afforded rights and then that user is deleted, Windows reassigns that user a cryptic name under "Security". But that's not happening so where they come from I got no idea I just remove them.