Dim users() As String = My.Computer.Registry.Users.GetSubKeyNames()
 
For Each user As String In users
 
   Dim rkey As Microsoft.Win32.RegistryKey = _
     My.Computer.Registry.Users.OpenSubKey(user, False)
 
   If rkey IsNot Nothing Then
 
      Dim renv As Microsoft.Win32.RegistryKey = _
      rkey.OpenSubKey("Environment", false)
 
      If renv IsNot Nothing Then
         Dim envvars() As String = renv.GetValueNames
 
         '......
 
         For i As Integer = 0 To envvars.Length - 1
             Dim env_vl As Object = renv.GetValue(envvars(i))
         Next i
 
         renv.Close()
      End If
      rkey.Close()
   End If
Next user