When you delete an email from your Outlook inbox, the email isn’t actually gone. It’s sent to the Deleted Items folder, which is similar to the Recycle Bin on your Windows Desktop. When you close Outlook, the Deleted Items folder is not emptied which means your deleted emails continue to use disk space. Furthermore, a full Deleted Items folder can impact system performance.

Instead of manually emptying the Deleted Items folder, I recommend configuring Outlook to do so automatically when the application is closed. To accomplish this in Outlook 2010:

  1. From the File menu, click Options.
  2. From the Outlook Options window, click Advanced.
  3. In the right pane, under Outlook start and exit, click the Empty Deleted Items folder when exiting Outlook option.
  4. Click OK.