SSIS Variables

i have the following code that works fine if the path is hard coded, but when i just a variable i get an error.
        Dim objExcel As Object
        Dim objWorkbook As Object

        sDate = Right("00" & Year(Now()), 4) & Right("0" & Month(Now()), 2) & Right("00" & Day(Now()), 2)

        objExcel = CreateObject("Excel.Application")

        objExcel.Visible = False

--variable
        objWorkbook = objExcel.Workbooks.Open(Str(Dts.Variables("User::LTH_IP").Value) & sDate & ".xls", , , , " test")

--hard coded.
        'objWorkbook = objExcel.Workbooks.Open("C:\Development\Dashboard Feeds\adm" & sDate & ".xls", , , , "test")

        objExcel.DisplayAlerts = False

        objWorkbook.Password = ""
        objWorkbook.SaveAs("C:\Development\Dashboard Feeds\adm" & sDate & ".xls")


        objExcel.Quit()