You can delete any folder you created in the Folder Pane. Remember, when you delete a folder, you’re also deleting everything inside of it.
Note: If you think you might need that folder (and its contents) later, back it up to a data file before you delete it.
Right-click the folder you want to delete and click Delete Folder.
Click Yes to move the folder and its contents to the Deleted Items folder.
When you empty the Deleted Items folder, everything in it — including any folders you’ve deleted — is permanently erased.
Note: You can’t delete built-in folders, such as Inbox, Outbox, or Sent Items.