[Macsee]

Simon, true. I had another look at htaccess. There isn't any rewrite for images and there's no blocking of hotlinking of images, nothing except a www canonical rewrite.

Originally Posted by kh99

I think Lynne was hinting at this before, but anyway - the cleanup2 scheduled task removes any entries from the attachment table that are older than 1 hour and have contentid = 0. So the fact that you saw the record had contentid=0 seems to be the problem...

That makes sense. It appears that the contentid shouldn't be equal to 0 and I don't know what's causing it to default to zero.

I've opened the class_dm_threadpost.php file and the code you posted is in there starting exactly at 526. I wouldn't know how to go about the debugging though and I hate to impose any further.