How do I resolve "ERR_SSL_PROTOCOL_ERROR" with Vercel?

When browsing to your site, you may encounter the error "ERR_SSL_PROTOCOL_ERROR". In this article, we will explain why this error occurs and what changes you need to make to resolve it.

Why Does This Error Happen?

This error is usually a symptom of Internet Service Providers (ISPs) or corporate networks who can inspect TLS handshake packets and make dynamic decisions based on your domain's reputation. Reputation may be calculated by a variety of data sources and complex algorithms.


To work around the issue, you may wish to try navigating to the site from a different network or device.

To fix the issue, on corporate networks, you need to discuss the matter with the network administrator and explain why the block is uncorrect. For home and cellular networks, you need to discuss the matter directly with the relevant ISP.

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