Changing folder icon in Windows 7 problem.

Hello guys,

I have a problem,
i am currently creating an application for managing windows 7 styles in folder.

I have programmed everything but left the basic icon changer code for the end(big mistake).

What i want to do is to change the icon of a specified folder.

What i am trying is giving me an error saying that access to the file is denied. I am trying to edit the desktop.ini inside the folder.
My code is:

    Public Shared Sub ApplyStyle(ByVal Query As String)
        Dim Info As String() = Query.Split("|")
        Dim Name As String = Info(0)
        Dim Path As String = Info(1)
        Dim Icon As String = Info(2)
        If IO.File.Exists(Icon) = True Then
            If IO.Directory.Exists(Path) = True Then
                Dim Reader As New IO.StreamReader(Path & "\desktop.ini")
                Dim Data As New RichTextBox
                Data.Text = Reader.ReadToEnd
                Reader.ReadToEnd()
                If Data.Text.Contains("IconResource=") = True Then
                    Dim Line As Integer = Data.GetLineFromCharIndex(Data.Text.IndexOf("IconResource=")) ' 13
                    Dim Lines As String() = Data.Lines
                    Lines(Line) = "IconResource=" & Icon & ",0"
                    Data.Lines = Lines
                Else
                    Data.Text = "[.ShellClassInfo]" & vbNewLine & _
                                "IconResource=" & Icon & ",0" & vbNewLine & _
                                Data.Text
                End If
                Dim Writer As New IO.StreamWriter(Path & "\desktop.ini")
                Writer.Write(Data.Text)
                Writer.Dispose()
            Else
                MsgBox("Selected folder doesn't exist, please edit the preferences of the style to fix the problem.", MsgBoxStyle.Critical, "Error")
            End If
            Else
                MsgBox("Icon doesn't exists, unable to enable the style. Please edit the style preferences.", MsgBoxStyle.Critical, "Error")
            End If
    End Sub

Please help me because i need the app finished in a few weeks.