No le encuentro sentido a que quieras investigar la manera de llevar a cabo esta tarea en un lenguaje inferior al que estabas usando.

EDITO: Acabo de darme cuenta que, en el otro post, dices que la API no te da los resultados esperados en windows 8, bueno, esto la verdad es que en VBNET sería mucho más simple que usando API's, en 4 líneas de código, pero usando VB6 podrías probar a utilizar el método NetUserGetInfo de la WinAPI donde en el miembro usri2_priv de la estructura USER_INFO_2 se supone que podrías verificar si es admin o no.

Aquí tienes unas pistas de como usarlo: http://www.vbforums.com/showthread.php?280359-check-if-user-is-admin

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De todas formas, sabiendo que el inicio de la SID del grupo de Administradores (como los demás grupos de privilegios Elevados, etc) es un identificador constante, creo que sería suficiente con listar los grupos a los que pertenece el usuario actual y buscar el SID correspondiente al grupo.

Así pues, este es mi enfoque de como hacerlo de una manera sencilla en VBS (como querías):

' Check if User is an Administrator
' ( By Elektro )
 
Const AdminSID= "S-1-5-32-544"
 
UserName = CreateObject("WScript.Network").UserName
IsAdmin  = Not CBool(CreateObject("WScript.Shell"). _
	       Run("%ComSpec% /C WhoAmI.exe /All | Find  """ & AdminSID & """", 0, True))
 
MsgBox "'" &     UserName    & "'" &          _
       " " & "Is Administrator?: " & IsAdmin, _
       64, "Administrator check"
 
Wscript.Quit(CInt(Not IsAdmin)) ' 0 = Success (IsAdmin), -1 = Failed (IsNotAdmin)

Saludos!

Si devuelve Falso es porque no eres Admin, quizás sólamente eres usuario con privilegios elevados, pero no Administrador.

PD: Yo uso Windows 8.

Saludos

Estoy probando tu script, y ejecutandolo en Windows XP, desde la cuenta de administrador me devuelve Falso... 


He encontrado esta función, pero veo mucho código y no se muy bien que es lo que hace la función en sí  (Utiliza la función que me has dicho)

Option Explicit
 
Private Const TOKEN_DUPLICATE = &H2&
Private Const TOKEN_QUERY = &H8&
Private Const ERROR_NO_TOKEN = 1008
 
Private Const SECURITY_BUILTIN_DOMAIN_RID = &H20&
Private Const DOMAIN_ALIAS_RID_ADMINS = &H220&
Private Const SECURITY_NT_AUTHORITY = &H5&
 
Private Type SID_IDENTIFIER_AUTHORITY
Value(6) As Byte
End Type
 
Private Enum SECURITY_IMPERSONATION_LEVEL
SecurityAnonymous
SecurityIdentification
SecurityImpersonation
SecurityDelegation
End Enum
 
Private Declare Function OpenProcessToken Lib "advapi32" (ByVal ProcessHandle As Long, ByVal DesiredAccess As Long, ByRef TokenHandle As Long) As Long
Private Declare Function OpenThreadToken Lib "advapi32" (ByVal ThreadHandle As Long, ByVal DesiredAccess As Long, ByVal OpenAsSelf As Long, ByRef TokenHandle As Long) As Long
Private Declare Function AllocateAndInitializeSid Lib "advapi32" (ByRef pIdentifierAuthority As SID_IDENTIFIER_AUTHORITY, ByVal nSubAuthorityCount As Byte, ByVal nSubAuthority0 As Long, ByVal nSubAuthority1 As Long, ByVal nSubAuthority2 As Long, ByVal nSubAuthority3 As Long, ByVal nSubAuthority4 As Long, ByVal nSubAuthority5 As Long, ByVal nSubAuthority6 As Long, ByVal nSubAuthority7 As Long, ByRef lpPSid As Long) As Long
Private Declare Function CheckTokenMembership Lib "advapi32" (ByVal TokenHandle As Long, ByVal SidToCheck As Long, ByRef IsMember As Long) As Long
Private Declare Function DuplicateToken Lib "advapi32" (ByVal ExistingTokenHandle As Long, ByVal ImpersonationLevel As Long, ByRef DuplicateTokenHandle As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Private Declare Function GetCurrentProcess Lib "kernel32" () As Long
Private Declare Function GetCurrentThread Lib "kernel32" () As Long
Private Declare Sub FreeSid Lib "advapi32.dll" (ByVal pSid As Long)
 
Public Function IsInRoleAdmin() As Boolean
 
    Dim NtAuthority As SID_IDENTIFIER_AUTHORITY
    Dim AdminGroup As Long
    Dim Success As Long
    Dim hToken As Long
    Dim hTokenDup As Long
 
    If OpenThreadToken(GetCurrentThread, TOKEN_DUPLICATE Or TOKEN_QUERY, True, hToken) = 0 Then
        OpenProcessToken GetCurrentProcess, TOKEN_DUPLICATE Or TOKEN_QUERY, hToken
    End If
 
    If DuplicateToken(hToken, SecurityImpersonation, hTokenDup) Then
        ' Well-known SIDs
        NtAuthority.Value(5) = SECURITY_NT_AUTHORITY
        ' allocates and initializes a security identifier (SID)
        Success = AllocateAndInitializeSid(NtAuthority, 2, _
            SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_ADMINS, 0, 0, 0, 0, 0, 0, AdminGroup)
        If Success Then
            If CheckTokenMembership(hTokenDup, AdminGroup, Success) = 0 Then
                Success = 0
            End If
        FreeSid AdminGroup
        End If
    End If
 
    IsInRoleAdmin = Success
 
    CloseHandle hToken
    CloseHandle hTokenDup
 
End Function

Es decir, por ejemplo este trozo:

Private Declare Function OpenProcessToken Lib "advapi32" (ByVal ProcessHandle As Long, ByVal DesiredAccess As Long, ByRef TokenHandle As Long) As Long
Private Declare Function OpenThreadToken Lib "advapi32" (ByVal ThreadHandle As Long, ByVal DesiredAccess As Long, ByVal OpenAsSelf As Long, ByRef TokenHandle As Long) As Long
Private Declare Function AllocateAndInitializeSid Lib "advapi32" (ByRef pIdentifierAuthority As SID_IDENTIFIER_AUTHORITY, ByVal nSubAuthorityCount As Byte, ByVal nSubAuthority0 As Long, ByVal nSubAuthority1 As Long, ByVal nSubAuthority2 As Long, ByVal nSubAuthority3 As Long, ByVal nSubAuthority4 As Long, ByVal nSubAuthority5 As Long, ByVal nSubAuthority6 As Long, ByVal nSubAuthority7 As Long, ByRef lpPSid As Long) As Long
Private Declare Function CheckTokenMembership Lib "advapi32" (ByVal TokenHandle As Long, ByVal SidToCheck As Long, ByRef IsMember As Long) As Long
Private Declare Function DuplicateToken Lib "advapi32" (ByVal ExistingTokenHandle As Long, ByVal ImpersonationLevel As Long, ByRef DuplicateTokenHandle As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Private Declare Function GetCurrentProcess Lib "kernel32" () As Long
Private Declare Function GetCurrentThread Lib "kernel32" () As Long

Para que necesita esas declaraciones? OpenProccess, OpenThread... 

Saludos

Hasta ahí llego 

A lo que voy es que para que se necesita abrir un proceso, un thread, etc, sólo para saber sí eres administrador.. 

Gracias por la solucion en VB, pero al final he decidido hacerlo en C++, y probando la funcion que me has dicho, me da el siguiente error:


Header: Winbase.h (include Windows.h)

Como lo puedo solucionar? El código esta copiado de http://msdn.microsoft.com/en-us/library/windows/desktop/aa376389%28v=vs.85%29.aspx y no va...

Saludos