Why have a lot of uploaded images been replaced by question marks ?
If you look on a thumbnail gallery under anyone's user name you will see many images (particularly older ones) have been replaced by a question mark symbol.
Can you give me the URL of a page with the problem?
If you select the thumbnail gallery option and for the sake of argument enter my user name, you will see hundreds of question marks where images should be. It's the same for any other user as well. I'll try and find a specific URL for you as well.
Chris Brooks - www.dragonfly-images.co.uk
My Flickr site - www.flickr.com/photos/ceb1298
I see it now.
The images won't be lost. Most likely an issue with generating the thumbnails. I'll investigate....