firstly, i'm not sure how to re-produce it, however, i do have a theory on how it may be possible(see below).
the bug is as such:
load a save game manually(via selecting load from the menu screen)
select the infected save file.
the game well begin to load
a message well pop up saying that the file in question contain's DLC that is not found on your system, some parts of the game may not be accessible, do you want to continue?
regardless of continuing or not, i then receive the message that the save device cannot be accessed any longer, and i am thrown back to the main menu, regardless if being loaded from within game, of from the main menu.
this has infected all 3 of the save files present, i have 2 main save files, and the auto-save, all 3 now display this message.
when i first encountered this bug, it was with the auto-save file, i was still able to load my manual saves however
later, this bug re-appeared, after i had entered a new area, i wanted to test something, so i have saved the game, i went and tried to use two magazines at once so i could access a terminal, i discovered that you can only activate one magazine, which was why i saved in case it wasn't possible, so i procedded to re-load from my previous save, which gave me the above error message, i tried my other save, same message, and the same message for the auto-save.
i do not see how 3 separate save files could have become corrupted, nor do i want to know, either way, i do not actually believe they are corrupted(image's of the last thing i saw are still visible, i just can't load them, without that dialog appearing)
my current theory of re-producing the bug is untested, however it seems to have occurred after i save, i proceed to do an action, and if the action fails, in-game, i select to load the save, and the bug happens, i cannot gurantee that this is why the bug occurs, or an 100% solution.
i do not wish to restart the game, please, this is something that needs to be patched ASAP, i don't think i'd feel safe playing again, knowing that after several hours, i could simply lose all my data because of faulty programming.
edit: also note, i do not actual have any dlc for this game