Edit Template

If you want to make changes to a template, especially if you want to add Mail Merge Fields, you should use Template Designer

1. Open the Access Object that contains the fields
2. Mail Merge > Tools > Template Designer
3. In the Select Template dialog pick the template you want to edit. The dialog only shows templates it knows from the processes collection to be used with the current data source. If it is not listed, select 'Other' 
4. To continue click OK, or double-click the selected item.