When you delete a project, it is permanently removed from your database, so you can’t retrieve it. That is why we recommend changing the status of projects that you are no longer using instead of deleting them. You can mark such projects as Completed, Deferred, Cancelled, or Archived.
You can also mark tasks as closed, rather than deleting them.
Use the Archived status to disable older projects you no longer need ready access to. Archived projects do not display on the list of All projects or My Projects on the Project Management > Projects page.
To view archived projects:
Archived projects display in gray.
To view a closed task:
All closed tasks display.