Why do I have lock icons on some folder & how do I remove them

I have a relatively new machine and I have moved most of my folders and files from one to the other via a external drive.

I know there can be issues with ownership and permissions however I do not fully understand the way that works.

I am noticing that in a program Excel, Outlook, & other programs that if I go to File-Open and look at the dialogue box most of the folders in my "Libraries\documents" have a small lock icon on the lower left corner of the folder. However I do notice folders that I have recently created on the new machine do not have this icon.

If I go to the start menu and select documents (which opens up the same "Libraries\document" of which I have two locations referenced) I do not see these lock icons.

This is really a very minor problem, but more of a nuicence than anything else. I am hoping someone can explain to me why this is happening and if I can remove these lock icons.

Thanks,
Matt