Are there any additional system requirements to use your Stripe functionality?

Yes, for your Magento instance to work with Stripe payment gateway, it should have:

• HTTPS (SSL). We have a comprehensive guideline for configuring it in your Magento instance.
• TLS 1.2 or above. TLS is present on most Magento instances by default but (since June 13th, 2018) it should be updated to at least v1.2 - official Stripe guideline for this process.

If any of these is missing/misconfigured, Stripe will reject any payment attempts for such an instance.

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