Apparently your file is corrupt and if you don't have any backups there is not much you can do - keep your fingers crossed that Markus and his team can do magic.
But it can't be said often enough ... backup your files
This post was stickied back in OOTP17, but it should be moved each year once the new version comes out.
PSA: Back up your leagues!
I use the "zip-method" and didn't have the slightest problems.