To use Purolator in Shippo, you will need to register on their Resource Center website and request a Production Key using the link below. You will be provided with a Production Key, Production Key Password, and an Account Number.
Once registered, click on the "Ready for Production" button and follow the instructions on how to request the key (select the option: “I'm integrating Purolator E-Ship Web Services into a website or application that won’t be re-sold.”).
Once done, you will receive an email with your Production Key. Your Production Key will not be active immediately. As explained in the email, you should receive a call from Purolator within the next few days to activate it. If you do not hear from them you can reach them at 1-800-459-5599. Once activated, it will be ready to use in Shippo.
Please follow the steps to connect here—Carriers Supported by Shippo.