[2.0] List of SQL Srevers

[avrail]

well, i try to get the sql server list on my network
getting the names of the servers using c#
and here is what i done:
i added a refrance to use SQLDMO
here is the code i used to get the servers list

SQLDMO.Application fApp = new SQLDMO.ApplicationClass();
SQLDMO.NameList nl = (SQLDMO.NameList)fApp.ListAvailableSQLServers();
            foreach (string strServer in nl)
            {
                MessageBox.Show(strServer);
            }

this was the code and this was the Error Message that I get

Unable to cast COM object of type 'System.__ComObject' to interface
 
type 'SQLDMO.NameList'. This operation failed because the QueryInterface 
call on the COM component for the interface with IID '{10022406-E260-11CF-
AE68-00AA004A34D5}' failed due to the following error: No such interface 
supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE)).

can ay one help me? thanks alot