Hi guys, first post here I believe. I have a 2011 MBP on 10.9.5 and a couple programs just reset themselves without warning. I was using Firefox as per usual, and also running a virus scan using the Bitdefender app from the app store (used maybe once before). I saved and quit Firefox, left the room for a few minutes, and when I came back and restarted Firefox it was completely reset - saved session gone, bookmarks gone, extensions gone, history gone, etc. Also, I was signed out of Steam and Spotify desktop programs, and gfxCardStatus has suddenly begun giving pop-up notifications again. When I restarted the computer the wallpaper changed (the previous one had been set by Firefox). When I logged back into Steam, it didn't recognize the computer and I had to input a new security code, and all of my games had been uninstalled (yes, the entire game deleted from the SteamApps folder) and saves gone. Chrome was also reset, but I don't really use it. Also all my launchpad icons were rearranged. That's all I've noticed so far, Safari is unaffected and all other files are intact. Does anyone have any idea what might have happened? I really just want to restore my Firefox data, nothing else is a big deal, but I'd really like to know what caused this. I would just post up on the Mozilla forum, but since those other programs were affected, I'm not sure if Firefox caused the problem, or something else. Help please!