Go to My Account and then go to All My Downloads. You will find a button to reset your activation on the top of that page. You don't need access to the machine.
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.