Hello. You will have to open the document in the background in order to view that info. How I understand it: Every file that is referenced in your current assembly is technically open but you cant see it. You can check this with "ThisApplication.Documents.Count"
Use something like this to get the part number of suppressed parts from the bom
Dim oADoc As AssemblyDocument = ThisApplication.ActiveDocument
Dim oBOM As BOM = oADoc.ComponentDefinition.BOM
Dim oBOMView As BOMView = oBOM.BOMViews.Item(1)
For Each oRow As BOMRow In oBOMView.BOMRows
If oRow.ComponentOccurrences.Count = 0
filename = oRow.ReferencedFileDescriptor.FullFileName
Dim oDoc As Document
oDoc = ThisApplication.Documents.Open(filename, False)
partnumber = oDoc.PropertySets.Item(3).Item("Part Number").Value
MessageBox.Show(partnumber)
oDoc.Close
End If
Next