You were trying to insert HTML code. You only need a direct link which addresses to the image.
In photobucket, the easiest way to get this is from the thumbnail view in your album.
Hover over the picture you want and a drop-down list appears (see above). Select the bottom option "IMG code" and single left click it. You will see it briefly displays "copied"
Go back to your XMTS post (best have this open in another window or tab.) Right click and paste and this will insert the correct link and img tags for the image you want to display.
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