How do I create a Sandbox account for Payflow Pro (US, AU) or Website Payments Pro Payflow Edition (UK)?

Here's how:

Log in to your PayPal Manager account and verify that your account is active.
Log in to the PayPal Developer Portal.
Set up Business and Personal Sandbox test accounts (see How do I create a Sandbox test account?).
After you've created a Business Sandbox test account, create a ticket and ask to have your Payflow Pro (US, AU) or PayPal Website Payments Pro Payflow Edition (UK) account linked to the PayPal Sandbox Business Account you setup. Provide the email ID you used when you created your Business account in the Sandbox.
Once you're notified that your account has been updated, you can test against the PayPal Sandbox by using the Payflow Pilot Endpoint.

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