Wamp,
It appears that Yahoo Photos keeps track of sessions, so that you can not use their site to link pictures from them. The picture may show up for a little while, but the picture address will be invalid later on. I posted a pic here, it showed up for a while, but when I tried to access it later on, it was not there so I deleted the post.
If you wish to show pictures in your posts you will need to find a free website and start a website there and store your images there also. Most free servers do not allow you just to store images. If you need help, let me know.
What you were doing was correct, but due to the way Yahoo does things, it will not work for long. Don't get fustrated, you just need to know the rules on how certain site work. Until today, I did not realize that Yahoo Photos site ran that way. It definately does what it is supposed to.
Anyways, I put up an image for you so people could see it from the post...
<p align="center"><font size="4" color="#0000FF"><strong>The picture below is of Wamp's tank, not mine.</strong></font>
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