I have been experiencing black bars up the side of my screen ever since I installed the game on my new Laptop. It only happened when I played TS3 and TS2. I haven't played Medieval on it yet, so I can't be sure about it in TSM.
After I snapped yesterday, I switched my game resolution to 1366 x 768 (I believe) via game options. I also tweaked all of my graphics settings. I saved and quit the game (I made sure of it - I did these changes in my Mad Max Skillz Challenge File, and had made decent amount of progress). When I reloaded the game earlier to play my dynasty, I noticed around four major changes - my resolution had reset, the game asked me about edge scrolling, Agnes Crumplebottom had a memory notification (I turn the things OFF! They are the bane of my Simming Experience, I swear), And my Age Sliders had reset from Long to Normal. All of my other options are intact. The only game related things I did in between are the following - I cleared my caches, moved some save files, cleared my screenshots, emptied DCBackup and edited my Custom Music folder. That's it.
Did I mess something up in between? I just checked - I most certainly emptied DCBackup, not DCCache. I also noticed that ccmerged.package is still in my DCBackup folder - is this because it's self-respawning, or I shouldn't delete it? I definitely emptied it, I used Select All.
I'm running Windows 7.