I didn't explain properly what I am trying to do.
I need to search for each Heading 1 in the document and then see that there is no header on the same page.
oHeader.Range always seems to be an empty string even if there is a header on the page.
In contrast, oHeader.Range.Sections.First.Headers.Item(1).Range .Text always has a value even if there is no header on the page.