Help?

If you scroll down a bit, you'll see a post I made a few days ago about my inability to get a picture onto my header. If anyone has any ideas, hints or tricks, please let me know!

As I said before, I've tried the usual way more than once, and even tried it with a few different templates. The picture loads, but will not show up on the header! Could it be something wrong with my computer, or are others having the same problem?

The picture that is supposed to be on the header of this template doesn't even show up!

Help? Anyone?