It's NOT your PC (or Mac, or iPod, or iPad or netbook).
If you don't want to read some boring techie stuff just move on!
The forum runs on a server. The forum uses a programming language call PHP. This generates web pages in real-time and sends them to your web browser. No human needs to be involved after the initial coding stage. It's an automated system. Imagine having to get the comments one by one and then update the web pages! Nightmare. Instead, when we post our witty comments, the server applies the rules, updates its database, makes a new web page and sends the page back to your computer.
The server expects to find things in certain places. If they're not there that can have catastrophic (computer dies) or mild (default icon displayed) consequences. Smileys not appearing is obviously a mild condition. There are two main reasons why they won't appear:
1) The little pictures have been deleted.
2) The server's firewall is blocking access to "localhost"
Aha, I hear you ask, reaching for another Mythos - what is
localhost? We're all familiar with our computer talking to remote computers, like, for example the BBC's computers. But your computer can also contact itself as though it were a remote computer. This is known as
localhost and usually has an IP address of 127.0.0.0
The forum code talks to localhost a lot. If you right-click on a smiley that's got a place-holder funny little red triangle and page-turned-down icon you'll find that it's URL looks like this:
http://localhost/sanstefsmf/Smileys/default/cry.gifSo you can see that the forum code is asking for an image (cry.gif) via localhost. So the ways to failure are that the image, or folder, doesn't exist, or that something's blocking network access to localhost (which is VERY unusual). Users can't fix this. We are powerless.