We have a feature within the Unreal Engine folder that we wanted to make sure users are aware of for future use! If a user made a mistake that is difficult to fix, we have provided a backup system within the folders /unrealengine/launcher/backup/. This folder saves data so that, if a crash occurs or you need a backup copy of data you have created, it is saved for you!
Now, we realize that not everyone wants this feature, and we wanted to ensure that you can delete the folders within the backup folder (do not delete the backup folder itself). This is also very important to know as the data can build up fairly quickly, especially when working on large projects. If you notice an increase in the amount of space being used in your harddrive, a good place to check is the backup folder to see if it is holding a lot of data you simply no longer need.