java - Unrecognized SSL message, plaintext connection? Exception

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I have a java complied package to speak with the https server on net. Running the compilation gives the following exception:
javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
    at com.sun.net.ssl.internal.ssl.InputRecord.handleUnknownRecord(Unknown Source)
at com.sun.net.ssl.internal.ssl.InputRecord.read(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at sun.net.www.protocol.https.HttpsClient.afterConnect(Unknown Source)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(Unknown Source)
I think this is due to the connection established with the client machine is not secure.  Is there any way to configure the local machine or ports in order to connect to the remote https server?
                For the sake of Google search this is recently being returned as "Unrecognized record version TLS-0.0 , plaintext connection?"
– Jp_
                Oct 6, 2021 at 22:06
                I have the same error, and I solved when I started using http instead of https. But when I place the link in browser with https it works! And I need to perform a safe query. Any idea on how can I solve the problem?
– ccoutinho
                Mar 31, 2014 at 14:06
                @rsy When you 'placed the link ... with https' the browser would have changed to port 443 for you. You can do the same yourself. Indeed HttpURLConnection will automatically do it for you, if you don't specify a port at all.
– user207421
                Jun 9, 2014 at 23:54
                I assume that you can setup any port on your server to be HTTPS, it doesn't have to be a specific port?
– user3202835
                Aug 25, 2017 at 7:50
                @KarlSherwin It can be any port you like, subject to reservations, but if it isn't 443 you will have to cart that around yourself in all your URLs.
– user207421
                Apr 4, 2018 at 6:21
                Thanks a lot. Actually, I was using port 80 for an HTTPS connection. When I changed it to 443 it worked as expected.
– Vipul Verma
                Jun 11, 2021 at 11:29
You should have a local SMTP domain name that will contact the mail server and establishes a new connection as well you should change the SSL property in your programming below 
javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection
 props.put("mail.smtp.socketFactory.fallback", "true"); // Should be true
                In my case that worked, thanks! javax.mail.MessagingException: Could not connect to SMTP host: mail.livemusicgo.com, port: 25;   nested exception is:         javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
– surfealokesea
                Apr 22, 2014 at 5:49
                @surfealokesea The question is about HTTP and HTTPS, and an answer or a personal experience about SMTP isn't relevant.
– user207421
                Jul 3, 2018 at 10:03
                Yes but this is not just for him it is for other users that are having this same 'unrecognized ssl message'. +1 to you, Thobith
– sam1370
                Aug 27, 2018 at 0:36
                I also Had "javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?"  Error and this worked out for me. In my case it was SMTP
– Pasan Jayawickrama
                Jun 30, 2022 at 14:36
                can you please explain in brief how to resolve, me too facing same issue in my company right ow
– Nitesh
                Sep 6, 2019 at 5:51
                No, you got the error when accessing the HTTP port via HTTPS. Read the error message. You connected to a plaintext target. The situation you described wouldn't have caused an SSLException, as you wouldn't have been using SSL.
– user207421
                Jul 2, 2015 at 22:05
Adding this as an answer as it might help someone later.
I had to force jvm to use the IPv4 stack to resolve the error. My application used to work within company network, but while connecting from home it gave the same exception. No proxy involved. Added the jvm argument 
   -Djava.net.preferIPv4Stack=true and all the https requests were behaving normally.
@Bean
public AmazonDynamoDB amazonDynamoDB() throws IOException {
    return AmazonDynamoDBClientBuilder.standard()
            .withCredentials(
                    new AWSStaticCredentialsProvider(
                            new BasicAWSCredentials("fake", "credencial")
            .withClientConfiguration(new ClientConfigurationFactory().getConfig().withProtocol(Protocol.HTTP))
            .withEndpointConfiguration(new AwsClientBuilder.EndpointConfiguration("localhost:8443", "central"))
            .build();
It works for me using unit test.
Hope it's help!
I face the same issue from Java application built in Jdevelopr 11.1.1.7 IDE. I solved the issue by unchecking the use of proxy form Project properties.
You can find it in the following:
Project Properties -> (from left panle )Run/Debug/Profile ->Click (edit) form the right panel -> Tool Setting from the left panel -> uncheck (Use Proxy) option.
i solved my problem using port 25 and Following prop
mailSender.javaMailProperties.putAll([
                "mail.smtp.auth": "true",
                "mail.smtp.starttls.enable": "false",
                "mail.smtp.ssl.enable": "false",
                "mail.smtp.socketFactory.fallback": "true",
                earlier you used smtps then as a temporary workaround you fallback to smtp. These errors are related to https/smtps.
– Rohit Gaikwad
                Oct 7, 2022 at 6:17
In case you use Jetty version 9 or earlier you need to add it to jetty
RUN java -jar ${JETTY_HOME}/start.jar --add-to-startd=https
and according to this
Jetty: How to use SSL in Jetty client side
from Jetty version 10 it should work out of the box
It worked for me now, I have change the setting of my google account as below:      
        System.out.println("Start");
        final String username = "myemail@gmail.com";
        final String password = "************";
        Properties props = new Properties();
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.host", "smtp.gmail.com");
        props.put("mail.smtp.port", "465");
        props.put("mail.transport.protocol", "smtp");
        props.put("mail.smtp.starttls.enable", "true");
        props.put("mail.smtp.starttls.enable", "true");
        props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
         Session session = Session.getInstance(props,
                  new javax.mail.Authenticator() {
                    protected PasswordAuthentication getPasswordAuthentication() {
                        return new PasswordAuthentication(username, password);
        try {
            Transport transport=session.getTransport();
            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress("myemail@gmail.com"));//formBean.getString("fromEmail")
            message.setRecipients(Message.RecipientType.TO,InternetAddress.parse("myemail@gmail.com"));
            message.setSubject("subject");//formBean.getString(
            message.setText("mailBody");
            transport.connect();
            transport.send(message, InternetAddress.parse("myemail@gmail.com"));//(message);
            System.out.println("Done");
        } catch (MessagingException e) {
            System.out.println("e="+e);
            e.printStackTrace();
            throw new RuntimeException(e);
Though I have enabled SSL and TSL while running program in this link of same post. I spend a lot of time but than I realized and found this link.
And done 2 following steps and setting control in google. : 
Disable the 2-step verification (password and OTP)
Enabling to allow to access less secure app(Allow less secure apps:
ON.)
Now I am able to send mail using above program.
I got the same issue and it got resolved by setting "proxyUser" and "proxyPassword" in system properties.
System.setProperty("http.proxyUser", PROXY_USER);
System.setProperty("http.proxyPassword", PROXY_PASSWORD);
along with "proxyHost" and "proxyPort"
System.setProperty("http.proxyHost", PROXY_ADDRESS);
System.setProperty("http.proxyPort", PROXY_PORT);
Hope it will work.
                It will work if you are using the Apache HTTP client and you got an authorization exception. It will not work to solve the problem stated by the OP.
– user207421
                Jul 3, 2018 at 10:04
I was facing this exception when using Gmail.
In order to use Gmail I had to turn ON "Allow less secure apps".
This Gmail setting can be found at https://www.google.com/settings/security/lesssecureapps after login the gmail account.
I've got similar error using camel-mail component to send e-mails by gmail smtp. 
The solution was changing from TLS port (587) to SSL port (465) as below:
<route id="sendMail">
  <from uri="jason:toEmail"/>
  <convertBodyTo type="java.lang.String"/>
  <setHeader headerName="Subject"><constant>Something</constant></setHeader>
  <to uri="smtps://smtp.gmail.com:465?username=myemail@gmail.com&amp;password=mypw&amp;to=someemail@gmail.com&amp;debugMode=true&amp;mail.smtp.starttls.enable=true"/>
</route>
If you're running the Java process from the command line on Java 6 or earlier, adding this switch solved the issue above for me:
-Dhttps.protocols="TLSv1"
				Unable to Send Mail - javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
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