Hi Henry
Not sure what macro you're using, but here is a macro by Doug Robbins, that
I modified to do what you want.
Good luck
Harold

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Option Explicit

Sub DuplicateSerialNumber()
'===============================================================================================================
' Create a bookmark named  "SerialNumber" in the document where you want the
Serial Number to appear.
' It can be in the header or footer if that is where you want the number.
Then create a macro containing the
' following commands to print the document.

' It will ask for the number of copies that you want to make and
sequentially number each copy.
' The first time this macro runs, the first copy will be numbered 1 and when
it finishes running,
' it will store in aSettings.Txt file the number that is one more that the
number on the last copy.
' The next time the macro is run, it will start numbering the copies from
that number. If when you first start,
' you want the numbers to start at some number other than 1, run the macro,
entering 1 as the number of copies
' and then open Settings.Txt file and replace the number in the file with
the number that you want as the first
' in the series.At any time thereafter, if you want the series to start at a
particular number,
' you can open that file and replace the number in it with the number that
you want to be the first in the series.

'If you want the Serial Number to appear in a particular format, e.g. 001,
002, etc, replace the line
'
'Rng1.Text = SerialNumber
'
'with
'
'Rng1.Text = Format(SerialNumber, "00#")
'================================================================================================================

Dim SerialNumber As String, Counter As Long
Dim Message  As String, Title  As String, Default  As String, NumCopies  As
Long
Dim Rng1 As Range
Dim i As Long

' Set prompt.
Message = "Enter the number of copies that you want to print"
' Set title.
Title = "Print"
' Set default.
Default = "1"

' Display message, title, and default value.
NumCopies = Val(InputBox(Message, Title, Default))
SerialNumber = System.PrivateProfileString("C:\Settings.Txt", _
"MacroSettings", "SerialNumber")

If SerialNumber = "" Then
   SerialNumber = 1
End If

Set Rng1 = ActiveDocument.Bookmarks("SerialNumber").Range
Counter = 0

While Counter < NumCopies
    For i = 0 To 1
         Rng1.Delete
         Rng1.Text = SerialNumber
         ActiveDocument.PrintOut
    Next
    SerialNumber = SerialNumber + 1
    Counter = Counter + 1
Wend

'Save the next number back to the Settings.txt file ready for the next use.
System.PrivateProfileString("C:\Settings.txt", "MacroSettings", _
       "SerialNumber") = SerialNumber

'Recreate the bookmark ready for the next use.
With ActiveDocument.Bookmarks
   .Add Name:="SerialNumber", Range:=Rng1
End With

ActiveDocument.Save

End Sub
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