For more information see TLS protocol version support in Schannel. Recommendations For TLS 1.3, target .NET Framework 4.8 or later. Do not specify the TLS version explicitly. Configure your code to let the OS decide on the TLS version. Perform a thorough code audit to verify you're not specifying a TLS or SSL version explicitly. Do not use SslProtocols.Default. (SslProtocols.Default specifies SSL3
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