NUL chars in text file

Hello all, I've moved some php/html plaintext files from a OCZ SSD to a hard drive for backup (everything worked great) and now to a second hard drive. The problem is that while the size appears to OK, they're full of NUL characters. Any thoughts? I can't seem to be able to attach one of the files to the thread, here is a link: https://dl.dropboxusercontent.com/u/2532807/sampleFile1.html