[vb6] impedire una seconda istanza del programma

[codice_alpha]

come da titolo.. come si fa?
grazie!

[Jupy64]

If App.PrevInstance Then
   MsgBox "Già in esecuzione!"
else
   .....
end if

[codice_alpha]

Public Sub Main()
Dim RetVal As Boolean
Dim conta as integer
Dim Process as object

On Error Resume Next
conta = 0
For Each Process In GetObject("winmgmts:").ExecQuery("Select * from
Win32_Process WHERE Name='TuoProgr.exe'")
conta = conta + 1
If conta > 1 Then
MsgBox "already Running...", vbOKOnly, "Get Out"
Close All
Exit Sub
End If
End If
Next
MainForm.Show
End Sub