Windows Audit Log How Do I Monitor What Time A User Logs On Or Off?

How do I monitor what time a user logs on or off? - windows audit log

I am using Windows 2003 Active Directory on a server and I need something, if a user has closed his team to identify and introduced himself during the day. I know that I physically go to your PC and check the Event Viewer, and decisions on that, but I wanted to do it secretly. I think that hard workers and their finished work before they say they are and no time to look at them and physically. I am the security event audit log in the Event Viewer on the server, but I think that's right, because it has several different events unsubscribe link shows all day and I know some of the distance from your PC.