Knowledgebase

No. The only thing that you will need to change is your license key that you will receive when upgrading. This can be changed through your store admin via the Store Settings page in your store's control panel (click on Settings on the top right and then on Store Settings).

Once this has been changed your store will automatically be switched over to the Professional/Ultimate edition. All other store information, like products, customers and orders will still be available and will not need any modifications. You don't even have to temporarily disable your site while changing your store's license key!