can't see pics

I'm sure its been asked and answered a hundred times but....looking at a fairly recent thread and the pics come up as little blue question marks (?). I am using a Mac. If I remember correctly, when i used a windows-based computer the unseen pics were little red x's.
What do I need to do to see the pics? Thanks

 

What browser are you using? Have you tried a different browser?

Could you post a link here to a thread where you can't see photos? We can see if they do or don't show up for other members.

Could be a broken image link, the images could have been taken offline for some reason, maybe a network congestion issue, the image might have been hot-linked from another site, could be a change in your browser settings... and the list goes on.