If you signed up for Cognitive Class and did not receive a confirmation email within 1 hour, check your junk/spam folder first. If the email is not there it may have been blocked by your company. The best and easiest alternative is to sign up by using the Google, Yahoo, Facebook or LinkedIn buttons provided in the sign up page of Cognitive Class. This way, you don't need to wait for a confirmation email because access would be immediate. Simply click on any of those buttons, provide your credentials for the selected site, and you will be automatically redirected to Cognitive Class. From then on, follow the same procedure to sign in to Cognitive Class.
If all fails, please log out and log in again to receive a new activation email.