Some servers require an active email address as the FROM address. I updated yours to use the same email address you had set as the TO address and that seems to have fixed it.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.