I see there are a few posts on this.
I am in the Vault3 quest where I have to go kill the dude to get the key to the maintenance wing's locked door. I get the key, save the game. then I proceed to the door and just before I enter, I save again. Enter the door, kill the fiends, then kill that master dude that has the chainsaw. I collect the quest required item from the cupboard, save again. then I exit Vault 3 and head off to the next part of the quest - vault 22 - I fast travel to somewhere so I am closer to Vault 22. I save the game again when I am out in the Mojave wasteland. So by now I have multiple saves.
Then, I get killed and the game freezes when it tries to load my previous save! I have to reboot the console, and if I try to load any of my previous saves, I get a message box stating that required downloadable content is not present, and then continuing to load will bring up another message saying selected save device is not present!!! This happens for the previous 5 or so saves.
My last working save is when I am about to kill the dude to get the key section. I have gone back a few times and gone through the Vault 3 section, then fast travelled to other areas and saved games only to find that they are corrupt as well.
I am 20 hours into the game - is it true the only fix is to start from scratch again?
I have deleted old saves and have installed the game locally - which makes no difference!
Do you think I can return the game to the shop for a refund/swap????
Cheers
