Really Simple SSL

Category: Common Issues & Warnings

Common issues with HSTS

There are several causes for HTTP Strict Transport Security (HSTS) not working correctly. The most common HSTS issues are listed in this article. Response error: Multiple HSTS headers (number of HSTS headers: 2) When you see this error the HSTS header has been set twice. The HSTS header

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Updating your payment method / renewal failing

How to update your payment method/card (billing method) You can update your payment method in the profile tab of your account page. The process of doing this slightly differs depending on if you are switching from/to PayPal or Credit Card. Please find below the instructions for

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cURL errors

What is cURL? cURL is a widely used method of transferring data from and to (web)servers via URLs. It is installed on most, if not all webservers which makes it an ideal tool to use. Really Simple SSL uses cURL for a number of things.

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cURL error 35: SSL connect error

The cURL error 35 can appear in the Really Simple SSL debug log when the CURL function cannot connect to your website using SSL. Curl often uses a different set of certificates, shipped with PHP. There are several things that can cause this problem, in

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ERR_SSL_VERSION_INTERFERENCE The ERR_SSL_VERSION_INTERFERENCE is an SSL related error that usually appears in Google Chrome and Firefox when a site (server) uses TLS1.3. The err_ssl_version_interference error can be solved in a number of ways. Some guides suggest disabling TLS1.3 entirely in your browser, however that isn’t

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