Increment a sequential number for each document created

Hello,
I am looking to increment a chronological number with each document creation based on this template.
I found this

Create a new file and save it as a template, under the name "order form," for example.

Create a macro named "AutoNew":

This macro stores in an auto-insertion named "number" the one assigned to the last document based on the order form template.

To initialize this auto-insertion, enter in the document the number that will be assigned to the first document (minus 1). Select this number and choose the command:

Word 2000 to 2003: Insert, AutoText-AutoText.
Word 2007 to 2010: Insert tab; Text group, Quick Parts, AutoText, Save Selection to AutoText Gallery

- Type the name of the insertion: "number".
- In the "Look in" list, select order form.dot(m) to save it in the template. Click Add (2000 to 2003) or OK (2007 to 2010).
- Clear the number that was entered, save the template and close it.

To start a new order form, choose File-New and double-click on the icon of the Order Form template. The numbering will be done and the document is automatically saved (be careful to be in the folder where the order form should be stored)

Macro to copy by Alt + F11, paste into ThisDocument, File, Close and return to Word

Sub AutoNew ()
num = ActiveDocument.AttachedTemplate.AutoTextEntries("number").Value
num = num + 1
ActiveDocument.AttachedTemplate.AutoTextEntries("number").Value = num
num = Right("0000" & num, 4)
Selection.TypeText Text:="Order Form No " & num
SendKeys "o"
ActiveDocument.SaveAs FileName:="Order Form " & num & ".doc"

But after several attempts, nothing works, an error message appears, I think it's because I'm working on WORD 2010

Can someone help me?
Thanks

Configuration: Windows Vista / Firefox 37.0