How to find and replace string in Footer of Word document in C#?

object replaceAll = MSWord.WdReplace.wdReplaceAll;

foreach (Microsoft.Office.Interop.Word.Section section in oDoc.Sections)
{
      Microsoft.Office.Interop.Word.Range footerRange = section.Footers[Microsoft.Office.Interop.Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Range;
      footerRange.Find.Text = "Some Text";
      footerRange.Find.Replacement.Text = "Replace Text";
      footerRange.Find.Execute(ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref missing, ref replaceAll, ref missing, ref missing, ref missing, ref missing);
                    }