Hi All, Very useful thing is present for Win NT/2000/2003 DC. They call it Userlock. UserLock? solves this by tracking, notifying, and reporting all logon/logoff activity on your domains; and by limiting the number of simultaneous connections under a same user name for an entire Windows NT/2000/2003 network. (http://www.isdecisions.com/index.cfm?p=products-UserLock) And what about Samba?