Problems in VBA and Word

I have an issue with the VB code I have written in VBA 6.5.  We have today moved to a new environment and all our systems have been upgraded from Office 2003, Windows XP, VBA 6.5 to Office 2010, Windows 7, VBA 7.
I have a word document which I have now saved from .doc to .docm because of all the macros.  When a command button on this document is pressed it opens up another word document that is not visible to the user.  It adds numerous data to the new document and saves it.  One of the things it does is adds information in the header.  This all used to work fine until the changes today.  Now everything works fine but the information that is meant to go into the header is actually put into the body of the document where the code is running from, i.e the wrong document.  Can anyone see anything in the code that might be causing this to happen?  I wouldn’t say I am particularly advanced in VB.

'Add job name and ref to the header
       If Documents(matrixdoc).ActiveWindow.View.SplitSpecial <> wdPaneNone Then
        Documents(matrixdoc).ActiveWindow.Panes(2).Close
    End If
    If Documents(matrixdoc).ActiveWindow.ActivePane.View.Type = wdNormalView Or ActiveWindow.ActivePane.View.Type = wdOutlineView Then
        Documents(matrixdoc).ActiveWindow.ActivePane.View.Type = wdPrintView
    End If
    Documents(matrixdoc).ActiveWindow.ActivePane.View.SeekView = wdSeekCurrentPageHeader
    Selection.MoveDown Unit:=wdLine, Count:=2
    Selection.EndKey Unit:=wdLine
    Selection.MoveRight Unit:=wdCharacter, Count:=1
    Selection.TypeText Text:=job_Name
    Selection.MoveDown Unit:=wdLine, Count:=1
    Selection.TypeText Text:=job_Ref
    Selection.MoveRight Unit:=wdCharacter, Count:=1
    Selection.EndKey Unit:=wdLine
    Selection.MoveRight Unit:=wdCharacter, Count:=1
    Selection.TypeText Text:=Date
    Selection.MoveUp Unit:=wdLine, Count:=1
    Selection.TypeText Text:=Initials
    Documents(matrixdoc).ActiveWindow.ActivePane.View.SeekView = wdSeekMainDocument