Can your friend open the copy from their sent folder in their email application? I ask because it is possible the file was corrupted in the send. If they can open it, how are you opening it? Did you copy the file from the email to your computer instead of trying to open it out of your email app?
Take care, Mike
You generally can not send .eps files through email. Mail servers do not know what an .eps file is and will damage the file 9 out of 10 times by trying to scan it for viruses or other content it might understand.
Have your friend compress the file in a .zip or .rar archive and send that.
Bingo. I had him zip the file before sending and it worked like a charm.