I have a problem with taking MAC-addresses list in Windows XP from Inno Setup installer.
I'm trying to write some code (took it from Get MAC address in Inno Setup):
function GetMacAddressesList(out List: Array of String): Integer;
var
    I: Integer;
    WQLQuery: string;
    WbemLocator: Variant;
    WbemServices: Variant;
    WbemObject: Variant;
    WbemObjectSet: Variant;
begin
    Result := 0;
    WbemLocator := CreateOleObject('WbemScripting.SWbemLocator');
    WbemServices := WbemLocator.ConnectServer('localhost', 'root\cimv2');
    WQLQuery := 'Select * from Win32_NetworkAdapterConfiguration where IPEnabled=true';
    WbemObjectSet := WbemServices.ExecQuery(WQLQuery);
    if not VarIsNull(WbemObjectSet) and (WbemObjectSet.Count > 0) then
    begin
        Result := WbemObjectSet.Count;
        SetArrayLength(List, WbemObjectSet.Count);
        for I := 0 to WbemObjectSet.Count - 1 do
        begin
            WbemObject := WbemObjectSet.ItemIndex(I);
            if not VarIsNull(WbemObject) then
            begin
                List[I] := WbemObject.MACAddress;
                StringChange(List[i], ':', '');
                StringChange(List[I], '-', '');
            end;
        end;
    end;
end;
And I have a problem with ItemIndex method. It appears only in Windows Vista. How can I do this on XP? I really don't know, because every solution, that I have found in Internet doesn't work. May be because in Inno Setup libraries there is no such type as IEnumVariant and I can't iterate by SWbemObjectSet with for each obj in objset syntax... 
I was also trying to get SWbemObject with Item method:
WbemObject := WbemObjectSet.Item('Win32_NetworkAdapterConfiguration.Index=' + IntToStr(I));
but it returns error
SWbemObjectSet: not found
Can anybody help me? Has this problem some solution?