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Your store should be running on Magento 2 version 2.1.x.; 2.2.x, 2.3.x
Video Tutorial
Widget Connector width 853 url https://www.youtube.com/watch?v=YPIJgfm0Ljg&t=1s height 480
Configuration
Firstly, you have to configure the SagePay Payment Extension at Magento back end by clicking on Stores > Configuration > Sales > Payment Methods > SagePay Payment Gateway.
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