In my case, the root & intermediate certificates was successfully installed but I still got "Trust anchor for certification path not found." exception!. After digging the android document, found out that by default, secure connections (using protocols like TLS and HTTPS) from all apps trust the pre-installed system CAs, and apps targeting Android 6.0 (API level 23) and lower also trust the user-added CA store by default. If your app running on a OS with api level higher than 23 you should explicitly allow the app to trust user-added CA by adding its address to network_security_config like bellow:

<domain-config>
        <domain includeSubdomains="true">PUT_YOUR_SERVER_ADDERESS</domain>
        <trust-anchors>
            <certificates src="user" />
        </trust-anchors>
</domain-config>

在姜饼手机，我总是得到这个错误:信任锚没有找到Android SSL连接，即使我设置依赖于我的证书。

下面是我使用的代码(在Scala语言中):

object Security {
    private def createCtxSsl(ctx: Context) = {
        val cer = {
            val is = ctx.getAssets.open("mycertificate.crt")
            try
                CertificateFactory.getInstance("X.509").generateCertificate(is)
            finally
                is.close()
        }
        val key = KeyStore.getInstance(KeyStore.getDefaultType)
        key.load(null, null)
        key.setCertificateEntry("ca", cer)

        val tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm)
    tmf.init(key)

        val c = SSLContext.getInstance("TLS")
        c.init(null, tmf.getTrustManagers, null)
        c
    }

    def prepare(url: HttpURLConnection)(implicit ctx: Context) {
        url match {
            case https: HttpsURLConnection ⇒
                val cSsl = ctxSsl match {
                    case None ⇒
                        val res = createCtxSsl(ctx)
                        ctxSsl = Some(res)
                        res
                    case Some(c) ⇒ c
                }
                https.setSSLSocketFactory(cSsl.getSocketFactory)
            case _ ⇒
        }
    }

    def noSecurity(url: HttpURLConnection) {
        url match {
            case https: HttpsURLConnection ⇒
                https.setHostnameVerifier(new HostnameVerifier {
                    override def verify(hostname: String, session: SSLSession) = true
                })
            case _ ⇒
        }
    }
}

下面是连接代码:

def connect(securize: HttpURLConnection ⇒ Unit) {
    val conn = url.openConnection().asInstanceOf[HttpURLConnection]
    securize(conn)
    conn.connect();
    ....
}

try {
    connect(Security.prepare)
} catch {
    case ex: SSLHandshakeException /*if ex.getMessage != null && ex.getMessage.contains("Trust anchor for certification path not found")*/ ⇒
        connect(Security.noSecurity)
}

基本上，我在自定义证书上设置了信任。如果失败，我就禁用安全机制。这不是最好的选择，但这是我所知道的对于老旧和有问题的手机的唯一选择。

这个示例代码，可以很容易地翻译成Java。

产生信任锚错误的原因有很多。对我来说，我只是想访问https://example.com/而不是https://www.example.com/。

因此，在开始构建自己的信任管理器(就像我做的那样)之前，您可能需要仔细检查您的url。

@Chrispix的解决方案是危险的!相信所有的证书允许任何人做一个人在中间攻击!只要向客户端发送任何证书，它就会接受它!

将您的证书添加到自定义信任管理器，如本文所述:通过HTTPS使用HttpClient信任所有证书

虽然使用自定义证书建立安全连接有点复杂，但它将为您带来所需的ssl加密安全，而没有中间人攻击的危险!

与公认的答案相反，您不需要自定义信任管理器，您需要修复您的服务器配置!

我在连接Apache服务器时遇到了同样的问题，该服务器错误地安装了dynadot/alphassl证书。我正在使用HttpsUrlConnection (Java/Android)连接，这是抛出-

javax.net.ssl.SSLHandshakeException: 
  java.security.cert.CertPathValidatorException: 
    Trust anchor for certification path not found.

实际的问题是服务器配置错误——用http://www.digicert.com/help/或类似工具测试，它甚至会告诉你解决方案:

证书不是由受信任的权威机构签署的(根据Mozilla的根存储进行检查)。如果您从受信任的权威机构购买了证书，则可能只需要安装一个或多个中间证书。请与您的证书提供商联系，以便在您的服务器平台上执行此操作。”

您也可以在openssl中查看证书:

Openssl s_client -debug -connect www.thedomaintocheck.com:443

你可能会看到:

验证返回码:21(无法验证第一个证书)

在前面的输出中:

depth=0 OU = Domain Control Validated, CN = www.thedomaintocheck.com
verify error:num=20:unable to get local issuer certificate
verify return:1
depth=0 OU = Domain Control Validated, CN = www.thedomaintocheck.com
verify error:num=27:certificate not trusted
verify return:1
depth=0 OU = Domain Control Validated, CN = www.thedomaintocheck.com
verify error:num=21:unable to verify the first certificate`

证书链将只包含1个元素(您的证书):

Certificate chain
 0 s:/OU=Domain Control Validated/CN=www.thedomaintocheck.com
  i:/O=AlphaSSL/CN=AlphaSSL CA - G2

．.． 但是应该引用链中的签名授权，回到Android信任的授权(Verisign, GlobalSign等):

Certificate chain
 0 s:/OU=Domain Control Validated/CN=www.thedomaintocheck.com
   i:/O=AlphaSSL/CN=AlphaSSL CA - G2
 1 s:/O=AlphaSSL/CN=AlphaSSL CA - G2
   i:/C=BE/O=GlobalSign nv-sa/OU=Root CA/CN=GlobalSign Root CA
 2 s:/C=BE/O=GlobalSign nv-sa/OU=Root CA/CN=GlobalSign Root CA
   i:/C=BE/O=GlobalSign nv-sa/OU=Root CA/CN=GlobalSign Root CA

配置服务器的说明(和中间证书)通常由颁发证书的机构提供，例如:http://www.alphassl.com/support/install-root-certificate.html

在安装了我的证书颁发者提供的中间证书之后，我现在在使用HttpsUrlConnection连接时没有错误。

In my case, the root & intermediate certificates was successfully installed but I still got "Trust anchor for certification path not found." exception!. After digging the android document, found out that by default, secure connections (using protocols like TLS and HTTPS) from all apps trust the pre-installed system CAs, and apps targeting Android 6.0 (API level 23) and lower also trust the user-added CA store by default. If your app running on a OS with api level higher than 23 you should explicitly allow the app to trust user-added CA by adding its address to network_security_config like bellow:

<domain-config>
        <domain includeSubdomains="true">PUT_YOUR_SERVER_ADDERESS</domain>
        <trust-anchors>
            <certificates src="user" />
        </trust-anchors>
</domain-config>