Express Checkout solution is a part of the PayPal Website Payments Pro solution. Thus, to use PayPal Express Checkout, you need to sign for a business account at PayPal and apply for PayPal Website Payments Pro.
Express Checkout payment solution works with any of the currencies supported by PayPal.
PayPal Express Checkout is a combination of the checkout process on your website, PayPal login and review pages on https://www.paypal.com, and PayPal Web Services API SOAP requests/responses. Express Checkout allows customers the option to pay quickly through PayPal.
Your customer always starts and completes his order on your website:
To use the PayPal API with the plug-in, you will need to obtain and upload a merchant certificate file. You can get the test certificate (Sandbox API) immediately, and obtaining the Live certificate (to use the plug-in API in live mode) takes some time because your application is to be approved by PayPal in this case.
To obtain the certificate:
PayPal will notify you by e-mail to let you know if you qualify for a Live Certificate.If you have requested a Sandbox Certificate, you can download it immediately from the API Certificate page.
To configure the PayPal Express Checkout plug-in:
GetTransactionDetails API URL - Enter the URL to be used by the plug-in to send transaction status requests to PayPal (default is https://api.paypal.com/2.0/).
Check Status period - You can set the frequency (in hours) for payments status polling, i.e., periodical automated plug-in requesting the payment gateway for transactions processing results. This is the plug-in feature that allows you to monitor payments processing on the payment gateway side with the pre-set frequency.
Note that if you enter the zero value, the plug-in will not check transaction status at all.
Server URL - enter the test API URL into this field (default is https://api-aa.sandbox.paypal.com/2.0/)
Express Checkout API URL - Enter the testing PayPal API URL into this field (default is https://api-aa.sandbox.paypal.com/2.0/
GetTransactionDetails API URL - Enter the URL to be used by the plug-in to send transaction status requests to PayPal in the test mode (default is https://api.sandbox.paypal.com/2.0/).
Test User - Enter your PayPal API Account Name as it was specified during your application for Sandbox API Certificate.
Test Password - Enter your PayPal API Account password as it was specified during your application for Sandbox API Certificate into the field.
Test Merchant certificate. Uploaded from PayPal API Sandbox Certificate. Specify the certificate file location on your local computer or click the Browse button and locate the file.