Problem Solved !!
I suspected a compatibility problem, IE8 and the forum, and mentioned this to my mate who 'built' the computer. He's a software and hardware designer, and web-sites are not his forte, but he suggested going into 'Tools', 'Compatibility View Settings' and setting the forum address to view as compatible.
Bingo!
I can now see the pics.
Thanks very much Wojtek, and Eric. I did try Firefox, but that wouldn't even show the attachments - but then, I didn't know about the compatibility thing at the time!