Originally Posted by Shibboleet
I can't test it properly right now because I'm having other problems with my connection, but I can tell you how to test it. Simply try to view the images through a proxy server - any of the ones on should work. If you can see the images properly through the proxy, then it's a problem with TalkTalk. If you can't see the images even with the proxy, then it's probably a problem with the image server.
The only problem you may have is that some forums block proxy sites to prevent spam. If this is the case, just copy the image address posted on the forum and paste that directly into the proxy.