if you sent the file from a windows box, to a unix box, it'll translate the newline characters from \r\n (windows format) to simply \n (unix format). You can't just replace all the \n's with \r\n, though, as any \n characters in the original file will be translated to \r\n, even if that's not how they originally were.
However, if it was the other way around, you should be able to replace \r\n with \n and it might work.
Also, mac systems use \r as the newline character, so you may be able to use that.
BTW, this is all theoretical, I've never actually tried it.
\n = 00001010 (binary)
\r = 00001101 (binary)
That may work. Might be an interesting experiment, anyway.