I have a domain with a working Let's Encrypt SSL certificate but my web application uses Flask/Python on port:5000. The certificate fails with an error: Error code: SSL_ERROR_RX_RECORD_TOO_LONG (under Firefox; this just means the certificate is invalid I think). Any idea why and what I can do to solve this problem? Thanks, Cliff
I guess the error means that you try to access an http url by https. So it's not an invalid cert, it's just no SSL at all. Try to access this port by http, if this works, then you know that the service has no SSL configured.
