Detect who is logged on to remote Windows machines

not a GUI, but:

for /L %x in (2,1,254) do psloggedon \\172.21.0.%x

will do a scan from 172.21.0.2-254. You can also nest:

for /L %z in (16,1,31) do for /L %x in (1,1,254)  do psloggedon \\172.21.%y.%x

This will scan the 172.21.{16-31}.x subnets.

I found this script. It scans a whole domain and gives you a nice output (computer name and user name).

whoisloggedinwhere.bat > users.txt

@echo off
setlocal
for /f "Tokens=1" %%c in ('net view /domain:"%USERDOMAIN%"^|Findstr /L /C:"\\"') do (
 for /f "Tokens=*" %%u in ('PsLoggedOn -L %%c^|find /i "%USERDOMAIN%\"') do (
  call :report %%c "%%u"
 )
)
endlocal
goto :EOF
:report
set work=%1
set comp=%work:~2%
set user=%2
set user=%user:"=%
call set user=%%user:*%USERDOMAIN%\=%%
@echo %comp% %user%

This script uses PsLoggedOn.

Try nbtstat -a <computername>

I write the user name into the computer description property using a logon script, which lets me see everything in AD Users & Computers, do searches on it, and so on. Very handy.

If the servers are running Terminal Services, you can use Terminal Services Manager to view the servers in a domain and who is logged on to them. It is GUI and can be found under

Start -> Administrative Tools -> Terminal Services Manager

qwinsta is another dos command, but it'll still only give you one at a time...

C:\>qwinsta /server:test_srv
 SESSIONNAME       USERNAME                 ID  STATE   TYPE        DEVICE
 console           test_usr                  0  Active  wdcon
 rdp-tcp                                 65536  Listen  rdpwd

You can detect a user being locally logged on to a workstation by querying WMI through the following PowerShell script. It returns the name of whoever is logged on locally or the empty string.

function logged_in($host_name) {
    (get-wmiobject -class Win32_ComputerSystem -computername $host_name `
        -namespace "root\CIMV2").UserName
}

I'm not sure where I got it but I have this code laying around that shows users on a machine. You can wrap this in a for each loop to scan a bunch of machines. I would say that if you want to know who's logged on to a system the simplest way is to turn on login auditing and look at (or query) the security log. Here's the code to see who's on at any given moment:

' PARAMETERS
'
strComputer = "machineName"   ' use "." for local computer 
strUser = "domain\user" ' comment this line for current user
strPassword = "password" ' comment this line for current user

' CONSTANTS
'
wbemImpersonationLevelImpersonate = 3
wbemAuthenticationLevelPktPrivacy = 6

'=======================================================================
' MAIN
'=======================================================================

' Connect to machine
'
If Not strUser = "" Then

    ' Connect using user and password
    '
    Set objLocator = CreateObject("WbemScripting.SWbemLocator")
    Set objWMI = objLocator.ConnectServer _
        (strComputer, "root\cimv2", strUser, strPassword)
    objWMI.Security_.ImpersonationLevel = wbemImpersonationLevelImpersonate
    objWMI.Security_.AuthenticationLevel = wbemAuthenticationLevelPktPrivacy

Else

    ' Connect using current user
    '
    Set objWMI = GetObject("winmgmts:{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2") 

End If

' Get OS name
'
Set colOS = objWMI.InstancesOf ("Win32_OperatingSystem")

For Each objOS in colOS
    strName = objOS.Name
Next

If Instr(strName, "Windows 2000") > 0 Then

    '-------------------------------------------------------------------
    ' Code for Windows 2000
    '-------------------------------------------------------------------

    ' Get user name
    '
    Set colComputer = objWMI.ExecQuery("Select * from Win32_ComputerSystem")

    For Each objComputer in colComputer
        Wscript.Echo "User: " & objComputer.UserName
    Next

    ' ------------------------------------------------------------------

Else

    ' ------------------------------------------------------------------
    ' Code for Windows XP or later
    ' ------------------------------------------------------------------

    ' Get interactive session
    '
    Set colSessions = objWMI.ExecQuery _ 
          ("Select * from Win32_LogonSession Where LogonType = 2") 

    If colSessions.Count = 0 Then 
        ' No interactive session found
        '
        Wscript.Echo "No interactive user found" 
    Else 
        'Interactive session found
        '
        For Each objSession in colSessions 

            Set colList = objWMI.ExecQuery("Associators of " _ 
            & "{Win32_LogonSession.LogonId=" & objSession.LogonId & "} " _ 
            & "Where AssocClass=Win32_LoggedOnUser Role=Dependent" ) 

            ' Show user info
            '
            For Each objItem in colList 
                WScript.Echo "User: " & objItem.Name 
                WScript.Echo "FullName: " & objItem.FullName 
                WScript.Echo "Domain: " & objItem.Domain 
            Next 

            ' Show session start time
            '
            Wscript.Echo "Start Time: " & objSession.StartTime 
        Next 
    End If 

    ' ------------------------------------------------------------------

End If

'=======================================================================

I'm surprised nobody has mentioned loggedon2 yet, which I've been using for quite a few years. It's the GUI implementation you asked for and is available here.