burton

Can somebody confirm this? Is there no way to recover the files other than to format first they retry?

Bad solution. I downloaded Handy Recovery because I also got the "unable to read boot sector" error message. But after installing and accessing the partition, it says "No valid supported file system present on the volume". So back to square 1... I'm going to try out UndeletePlus next, though I think there is no other solution than to format.