Register for a free KPN Developer account. This account will grant you access to the KPN Things Portal with a freemium registration.
After registration you receive an activation email. It could take some time. Click the activation link (Stel uw wachtwoord in via accountbeheer) in the email and create a password. Now your KPN Developer account is activated.
Log in to the KPN Developer Portal
After registration you will end on a login page asking for your user name. Enter your email address here.
Then enter your newly created password and click Doorgaan to continue.