Illegaloperation WinWord

A friend sent me a document via e-mail.
I can open it and read it inside the e-mailprogram, but when i download it,and try to open it i get an illegal operation message.
The detail says: WINWORD caused an invalid page fault in module WINWORD.EXE at 017f:
30lef60f.
This is followed by: Registers: and an awful lot of numbers.
What is wrong here?