Visual Basic build error : I get 2 errors at line 70 and line 74 of making a keygenerator for XP Repair Pro6

when i finisherd every thing and built it it shows me these two errors 

1. TextBox2.Text = Generate(Strings.LCase(TextBox1.Text),
                                     Strings.LCase(MD5("xprp6-K0Wc0kf3Wcm5g-FEe43f")))
'MD5' is a type and cannot be used as an expression.


2. Public Shared Function MD5(ByVal InputStr As String) As String
Statement is not valid in a namespace.﻿

Please help, thanks