Platform-specific

    ERR_SSL_VERSION_OR_CIPHER_MISMATCH on Cloudflare

    Why it happens on Cloudflare

    Cloudflare's minimum TLS version setting is per-zone. Raising it to 1.3 blocks any client that cannot negotiate 1.3, which reads as a version mismatch to the visitor.

    The fix on Cloudflare

    SSL/TLS → Edge Certificates → Minimum TLS Version: set 1.2 unless you have a compliance reason for 1.3. Leave Opportunistic Encryption on.

    Is ERR_SSL_VERSION_OR_CIPHER_MISMATCH happening on your domain?

    The SSL check enumerates exactly which protocol versions and suites the server accepts, turning guesswork into a list.

    Free, no signup. Runs from outside your network, which is the only way to tell a server fault from a local one.

    If that didn't fix it

    Cloudflare has its own failure mode, but ERR_SSL_VERSION_OR_CIPHER_MISMATCH has a wider set of causes that apply everywhere. The most common one overall is: the server only supports tls 1.0 or 1.1.

    All causes and fixes for ERR_SSL_VERSION_OR_CIPHER_MISMATCH

    ERR_SSL_VERSION_OR_CIPHER_MISMATCH on other platforms and devices

    Nginx
    Chrome

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    Last verified: by the Lemwatch research team.