Replace a global default value with a default value

1. In the Database window, click Database Diagrams   under Objects, click the database diagram you want to open, and then click Design on the Database window toolbar.
2. If necessary, right-click the table and select Column Properties, Column Names, Keys, or Custom View from the shortcut menu. 
3. Assign a new default value to the column you want to change.
4. A message prompts you to permanently unbind the existing default in order for the new default to be applied. Choose OK.