"unable to read file" Error message Can someone help???

I am running the 2003 version of excel on windows XP. The file size of the
workbook I am trying to open is 70,084 KB.

I was working on the file today and saved it before I closed it. When I
emailed the link to my manager (link on the shared office network drive) he
said that he couldn't open it and received the "unable to read file" message.

I tried to open the file from my computer (I thought maybe it was a local
issue with his computer) and I received the same message.

I have tried seleting the file to open, selecting "open and recover" and
received the same message. Can anyone please offer some assistance? This
file took a long time to prepare and I thought by saving it before I closed
it, should offer a safeguard and since it's on the company network I thought
I would not have anything to worry about.