Excel Macro to convert list of files to pdf

Hi,

I have a number of wordfiles listed in an excel sheet, need to convert all the filenames listed to pdf. used below macro, giving error. I wonder if any one of you can help me in this regard.

Sub ExportFile()

For I = 1 To Range("A2").End(xlDown).Row
oldName = Cells(I, 1).Value
newName = Cells(I, 2).Value
Set Documents = GetObject(oldName)

ActiveDocument.ExportAsFixedFormat , Filename:=newName, ExportFormat:=wdExport.pdf


Next

End Sub