Security on Folder Level

We noticed that someone may have (intentionally or accidental) enabled folder level security on the mail folder on one of our Domino servers, where it now shows a padlock on the mail folder.I’d like to find out who may have done it.

Can someone please tell me how to do that quicker? If I open the server log within Domino, will it show it?

Should I be looking at the actual box’s log instead?

I understand this cahnge can be done on the Admin client, without having to go to the file level on the actual box.

I would appreciate some tips.