My saved household won't load

I can get into the game with no problem, but when I try to play with my household it tells me: 

"The game failed to load. Error Code: 102: eb51aGcf: babcbd5e. It is recommended that you relaunch the game."

I tried relaunching the game, checked for updates, tried clicking "repair", and restarted my computer, but nothing worked and it still pops up every time. I just installed some new mods, so that might be part of the issue. Can anybody give me CLEAR instructions on how I could fix this without losing my household's progress? (Also I don't own any extensions or packs so it's not related to that)