If you do not have your confirmation email available, or it has been longer than 10 days since your purchase of the product, then you can access your information in your user account at www.corel.com. You can log into your account at www.corel.com/youraccount.
Once you have logged into your account you will need to click on 'View Your Products' . You will then find a list of all your registered Corel products. Find your product and click on the link 'Get Serial' under the Serial Number column. This will show you a pop-up screen with your License Key/Serial Number, as well as your email address and the last 4 digits of the credit card you used to make the purchase.