Quoted from "Nihil Simile"

How do you attach pictures when I try I get Fatal error: PHP warning in file

I believe another poster already answered this in one of my threads.

in case you missed it, you need a upload your image to one of the image hosting companies (imageshack, photobucket, mediafire etc). most offer registration for free. alternately you could host the image yourself (free webspace you usually get with your ISP), tho better to use imageshack et al.
once uploaded, you'll be given a unique address which you copy and paste into the 'insert image' dialogue box of your reply post.