I recently imported a batch of NEF files from my Nikon D70 and converted them to DNG on import. 12 out of 20 files now appear to be damaged according to LR 2.5. This was not apparent (i.e. there was no exclamation point in a triangle symbol in the library module) until I tried to work on the file. I've tried opening them in photoshop and they will not open their either. I'm concerned with the large percentage of errors. I had no problem with any jpgs that I imported from another camera so I don't think there is a problem with my hard drive where the photos are stored. Any help would be appreciated.
Thanks,
Dennis