Just to add to the others comments: You can't, for good reason. This is a work-friendly site, and we want to keep it that way, so the people in charge of corporate networks don't block the site. If that happened, a lot of us would be unable to access info here which is really useful to do our jobs. The problem is that once you allow direct image posting you have to moderate the forums as well: every single question has to be vetted to make sure that nothing inappropriate is posted - because there are enough morons out there who will and do post images to any site because it s "funny". It wouldn't take many of those pictures to start us onto a blacklist, so we would have to moderate each and every question, answer, comment, and message. We don't have the resources to do that; we are all volunteers, and that kind of thing takes time and slows the posting of questions and responses. It's also serious boring, and people don't generally volunteer for dull stuff. So instead, all images are banned, and moderation can be a lot simpler - it can be as we do it now: after the fact. Ok, that means the one question in a thousand which would be improved by a question suffers. But the other 999 get a good, timely response. And to be honest, if you need to show us a picture, you are probably asking the wrong question anyway...
