请尝试将NSExceptionRequiresForwardSecrecy设置为false。但是，您的服务器确实满足传输层安全性（TLS）协议版本的最低要求，但您的服务器连接密码可能不支持前向保密。
协商的传输层安全性（TLS）版本必须是TLS 1.2。默认情况下，不使用TLS/SSL保护或使用旧版本的TLS/SSL进行连接的尝试将被拒绝。
连接必须使用AES-128或AES-256对称密码。
协商的TLS连接密码套件必须通过椭圆曲线Diffie-Hellman Ephemeral（ECDHE）密钥交换支持完全前向保密（PFS），并且必须是以下之一：
使用AES_256_GCM_SHA384时的最低血糖检测标准和最低血糖检测标准安全性分析-使用不良事件评估系统256_CBC_SHA384 TLS_ECDHE_安全性分析-使用不良事件评估系统128_CBC_SHA256 TLS_ECDHE_安全性分析-使用不良事件评估系统128_CBC_SHA

我终于解决了这个问题！我从.plist文件中取出了异常，并将以下代码添加到didReceiveChallenge委托方法中：

- (void)URLSession:(NSURLSession *)session
didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge
 completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition disposition, NSURLCredential * __nullable credential))completionHandler{
    NSLog(@"*** KBRequest.NSURLSessionDelegate - didReceiveChallenge IOS10");
    completionHandler(NSURLSessionAuthChallengeUseCredential, [NSURLCredential credentialForTrust:[[challenge protectionSpace] serverTrust]]);
}

这篇文章非常有用：http://timekl.com/blog/2015/08/21/shipping-an-app-with-app-transport-security/

为了避免完全破坏TLS（更不用说其他形式的身份验证），您应该做更多类似这样的事情：

- (void)URLSession:(NSURLSession *)session
    didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge
      completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition disposition,
                                  NSURLCredential *credential))completionHandler
    {
        NSURLProtectionSpace *protectionSpace = [challenge protectionSpace];
        if ([protectionSpace authenticationMethod] == NSURLAuthenticationMethodServerTrust) {
            // Load our trusted root certificate from the app bundle.
            SecTrustRef trust = [protectionSpace serverTrust];
            NSURL *certificatePath = [[NSBundle mainBundle] URLForResource:@"customRootCert" ofType:@"der"];
            NSData *certificateData = [NSData dataWithContentsOfURL:resourcePath];
            SecCertificateRef trustedCert = SecCertificateCreateWithData(NULL, (__bridge CFDataRef)certData);

            // Change the trust object to trust our root cert.
            trust = addAnchorToTrust(trust, trustedCert);

            SecTrustResultType secresult = kSecTrustResultInvalid;
            if (SecTrustEvaluate(trust, &secresult) != errSecSuccess) {
                // Something went horribly wrong.
                completionHandler(NSURLSessionAuthChallengeCancelAuthenticationChallenge, nil);
                return;
            }

            switch (secresult) {
                case kSecTrustResultUnspecified: // The OS trusts this certificate implicitly.
                case kSecTrustResultProceed: // The user explicitly told the OS to trust it.
                {
                    NSURLCredential *credential =
                        [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust];
                    completionHandler(NSURLSessionAuthChallengePerformDefaultHandling, credential)
                    return;
                }
                default:
                    /* It's somebody else's key/cert. Fall through. */
            }
            completionHandler(NSURLSessionAuthChallengePerformDefaultHandling, nil);
        } else {
            // If we aren't checking the server's public key, just use
            // the default behavior.
            completionHandler(NSURLSessionAuthChallengePerformDefaultHandling, nil);
        }
    }

请注意，这段代码未经编译和测试，因此请随意修复错别字和其他错误。