Some email messages I receive, have no message in the body of the email.

I've had this happen quite a few times. I had a family member send  an
email with an email address change and pictures of Lucy(He was using
stationary in Outlook Express), to both computers in my house. When I
opened his email on my computer there was no message in the body of the
email. When I opened the same
 message on my sons computer the message and pictures of Lucy was there.
We both are using Netscape Communicator 4.61, with the same preferences.
I am using a 450 Pentium lll computer with Windows98. My son has a 166
Pentium ll and is also using Windows98. I just can't figure it out. I've
had several emails that won't open. Any help would be greatly
appreciated. Thanks.
Richard

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