You can get your Live Lite 6 serial number by going to Ableton's website and registering Live Lite 5. Here is the process:

• Go to ableton.com
• Click on "Product Registration" on the left side of the page. Enter your Live Lite 5 serial number and complete the registration process.

• Log in to the account that you created during the registration process.

• Click on "Downloads" on the left side of the page.

• Click on "Upgrades."

• One of your upgrade options should be "Live Lite 5 to Live Lite 6 M-Audio Edition." Click on the "Get Free Product" button next to this option.

• Go to your cart and check out. The checkout button will probably also say "Get Free Product."

• You should be instantly redirected to a page displaying your Live Lite 6 Serial Number. This number will also be accessible by logging into the account you created during the registration process, and will be emailed to the email address you give them when you register. You will also be able to download Live Lite 6 if you should need to.