If you’re a Microsoft Office user, you’re probably familiar with how to delete emails and that it moves those emails into your Deleted Items folder. If you want to clean up that folder, you can either empty the whole folder or you can selectively delete emails for a 2nd time.
While in your Inbox, or any other folder, there’s some shortcut keys that you can use to permanently delete emails one time. With the email(s) highlighted, hold down the Shift key when you hit the Delete key and you’ll get a confirmation box asking if you want to permanently delete the email. Just click on Yes.
Remember, after you do this, your email is gone forever, there’s no way to get it back once Outlook syncs with your server.
As a reminder, remember to clean out your Sent Items folder too if you need to save some space.