To return the paragraph numbers for empty (or just spaces) paragraphs you could do a loop like this
Code:
Sub GetUsedParas()
Dim aPar As Paragraph, sList As String, i As Long
For i = 1 To ActiveDocument.Paragraphs.Count
If Len(Trim(ActiveDocument.Paragraphs(i).Range.Text)) = 1 Then
sList = sList & "," & i
End If
Next i
MsgBox Mid(sList, 2), vbInformation + vbOKOnly, "Empty Paragraphs List"
End Sub
You can team this up with Paul's code to open the document.