How can I tell who is logged in if I know Machine Name and IP Address

How can I tell who is logged in if I know Machine Name and IP Address. I ping the machine name and if gives me the IP address. Is there a toll that I can use to tell me who is logged in???

Thanks

nbtstat -A <IP address>

nbtstat -a <computername>

If it is a Windows NT workstation or computer, you can do the following:

Click "START", then "RUN"

Enter the following into the run dialog box:
\\<computername>\C$\winnt\profiles

where <computername> is the netbios name of the computer that you want to see who is logged onto.

Then click "OK"

The directory will open up as a new window. When you look at the directory, the folder name with the most recent "modified" date and time is the current (or most recently) logged in user.

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