In case you closed your file by mistake, and you require Recover Unsaved PowerPoint content, then PowerPoint has a feature of AutoRecover that will enable you to reclaim your work. After an accidental power outage or a crash, when you restart the power point, you are likely to see a Document Recovery brochure with the auto-saved ones. Provided that does not show up, you can search through unsaved presentations by clicking on the Recover Unsaved Presentations option. You are likely to recover the lost slides so long as AutoRecover is on.