Yes, mine were as well but the solution i posted in that thread worked on my PC.
There was also a reply after mine adding that you may have to first share the folder with everybody, and then un share it.
It seem if you share the folder the lock icon goes away. You then use the advanced share options to un share the folder as this doesn't put the lock icon on the folder, un like the share with Nobody option.
Im sure there are other ways but this worked for me.
I created a test folder and removed permissions for Authenticated Users and Users and this created the icon on the folder. Changing ownership didn't seam to make any difference. So to remove the icon give Authenticated Users or Users permissions to the folder.
I hadn't but gave it a go. By sharing the folder with everyone you are also adding the everyone group to the local permissions of the folder automatically. Then if you remove the share for everyone it removes the share but keeps the local permissions for the everyone group and as such removing the folder padlock icon.
No your ID shows as Full UserName (Computer name\Username) in the Security tab. Some info i found on Authenticated Users.
Should You Use the Authenticated Users Group?
The differences between the Everyone, Users, and Authenticated Users groups aren't apparent from the group names. In a nutshell, the Everyone group is the least secure of these groups because it does indeed include everyone. The Everyone group often contains the same set of users as the Users and Authenticated Users groups. However, if you've enabled the Guest account, you'll find that users who have logged on as Guest are members of Everyone but not members of Users or Authenticated Users.
The difference between the Users and Authenticated Users groups is a bit more esoteric. After all, if all users must authenticate, aren't all users authenticated users? If they are, why do you need a different group called Authenticated Users? The answer is that not all members of the Users group are authenticated. Windows networks include the ability to have computer-to-computer connections that involve null sessions. Computers use these sessions to exchange lists of shared folders, printers, and other network resources; workstations use null sessions to connect to domain controllers (DCs) before users authenticate to the domain. (For more information about null sessions, see the Microsoft articles "Local System Account and Null Sessions in Windows NT" at Microsoft Help and Support default.aspx?scid=kb;en-us;q132679 and "Restricting Information Available to Anonymous Logon Users" at Restricting information available to anonymous logon users.)
How I can set Authenticated Users Group in permissions?
Same as in here Change the permissions and take ownership of your files and folders | Windows Vista for Beginners
Scroll down to Changing Permissions section.
Add Authenticated Users instead of Administrator like they have.
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I 'll try this!