On my Windows 10 Pro, my Restore Points disappear after 30 minutes. There's plenty of room too (16 percent, 74GB). When they vanish, an Event Viewer entry (Volsnap) says "The oldest shadow copy of volume C: was deleted to allow shadow copies created afterward and marked for delete to be deleted.". I even have a Task set up to create Restore Points. They get created, then vanish 25-30 minutes later. I then created TWO sets of Restore Points. One set disappears in 30 minutes, then the next set disappears 30 minutes later. A few people in another forum have said their Restore Points vanish too. They're wondering if a recent Microsoft Update changed the way Restore Points behave.