Who is Logged on to a Computer

You can use WMIC command on Window xp pro or later version of OS to find out who is logged on to a computer.

WMIC /Node:RemoteComputerName ComputerSystem Get UserName

For Example:

>WMIC /Node:replicator ComputerSystem Get UserName
UserName
fzk
ske
tet
tue

Above are 4 users who are currently logged on to replicator.

Also, you can use the PSTools to find out who is logged on to a computer remotely by executing the following command:

PSLOGGEDON -L \\Remote ComputerName or PSEXEC file://remotecomputername/ NET NAME