I left my pc for 20 mins and when i came back everything from my HDD was lost. It shows 929/931 GB free. Literally everything. Dozens of games, i cant even uninstall them from steam since they are gone. I used the PC just fine before this happened, all my files on the D drive folders pictures everything gone. Pretty sure i lost everything, all i want to know what happened, why it happened and how can i make sure it doesnt happen again.