Macro Button disabled in protected worksheet

Hi Guys

I have managed to get a macro working that sends an email with attachment from my spreadsheet, with a little help from you very kind people.

It all works great until I protect the worksheet and it prevents the macro from working.
I've tried using Activesheet.unprotect ad Activesheet.protect at either and, but still no joy. Can anyone advise?

Apologies if it is obvious, but I'm pretty new to VBA.

Thanks in advance, VBA is below -

Sub Mail_Range()
' Works in Excel 2000, Excel 2002, Excel 2003, Excel 2007, Excel 2010, Outlook 2000, Outlook 2002, Outlook 2003, Outlook 2007, Outlook 2010.
    Dim Source As Range
    Dim Dest As Workbook
    Dim wb As Workbook
    Dim TempFilePath As String
    Dim TempFileName As String
    Dim FileExtStr As String
    Dim FileFormatNum As Long
    Dim OutApp As Object
    Dim OutMail As Object

    Set Source = Nothing
    On Error Resume Next
    Set Source = Range("B1:R1000").SpecialCells(xlCellTypeVisible)
    On Error GoTo 0

    If Source Is Nothing Then
        MsgBox "The source is not a range or the sheet is protected. " & _
               "Please correct and try again.", vbOKOnly
        Exit Sub
    End If

    With Application
        .ScreenUpdating = False
        .EnableEvents = False
    End With

    Set wb = ActiveWorkbook
    Set Dest = Workbooks.Add(xlWBATWorksheet)
    Source.Copy
    With Dest.Sheets(1)
        .Cells(1).PasteSpecial Paste:=8
        .Cells(1).PasteSpecial Paste:=xlPasteValues
        .Cells(1).PasteSpecial Paste:=xlPasteFormats
        .Cells(1).Select
        Application.CutCopyMode = False
    End With

    TempFilePath = Environ$("temp") & "\"
    TempFileName = "Selection of " & wb.Name & " " _
                 & Format(Now, "dd-mmm-yy h-mm-ss")

    If Val(Application.Version) < 12 Then
        ' You are using Excel 2000 or 2003.
        FileExtStr = ".xls": FileFormatNum = -4143
    Else
        ' You are using Excel 2007 or 2010.
        FileExtStr = ".xlsx": FileFormatNum = 51
    End If

    Set OutApp = CreateObject("Outlook.Application")
    Set OutMail = OutApp.CreateItem(0)

    With Dest
        .SaveAs TempFilePath & TempFileName & FileExtStr, _
                FileFormat:=FileFormatNum
        On Error Resume Next
        With OutMail
            .To = "random@rand.com"
            .CC = ""
            .BCC = ""
            .Subject = "Special Pricing Form for " & Range("D1")
            .Body = "Hi Guys" & Chr(13) & Chr(13) & "Please see attached Special Pricing form for " & Range("D1") & Chr(13) & Chr(13) & "Many Thanks" & Chr(13) & Range("G1")
            .Attachments.Add Dest.FullName
            ' You can add other files by uncommenting the following statement.
            '.Attachments.Add ("C:\test.txt")
            ' In place of the following statement, you can use ".Display" to
            ' display the e-mail message.
            .Send
        End With
        On Error GoTo 0
        .Close SaveChanges:=False
    End With

    Kill TempFilePath & TempFileName & FileExtStr

    Set OutMail = Nothing
    Set OutApp = Nothing

    With Application
        .ScreenUpdating = True
        .EnableEvents = True
    End With
End Sub

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

End Sub