Playing backed up save files

[Mister Z]

So, again, all my save files on DmC were deleted by who knows why (something to do with TexMod, I think). Luckily, I thought, I had backed up my saves last night so I hoped copy and pasting them into the game's folder would fix the problem. However, when I run the game and click on my save it claims it to be corrupt and asks me to overwrite it. In other words, I can't use my back ups for naught.

Does anyone know what to do to get around this or is it a lost cause and I have to do everything again?