email sending via wso2 identity server fails - wso2-identity-server

Question

I am using wso2 identity server 5.9.0 on my linux machine.
I am getting the error below while doing account creation.
I get message Email sent successfully, but at backend it throws error after some time and the mail is never received.
[2020-02-15 13:09:22,241] [725c9824-a414-44f4-9b4f-e5f8da8db48c] ERROR
{org.wso2.carbon.event.output.adapter.email.EmailEventAdapter} - Event
dropped at Output Adapter 'EmailPublisher' for tenant id '-1234',
Error in message format, Exception reading response
javax.mail.MessagingException: Exception reading response; nested
exception is:
java.net.SocketException: Connection timed out (Read failed)
at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:2460)
at com.sun.mail.smtp.SMTPTransport.ehlo(SMTPTransport.java:1699)
at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:744)
at javax.mail.Service.connect(Service.java:366)
at javax.mail.Service.connect(Service.java:246)
at javax.mail.Service.connect(Service.java:195)
at javax.mail.Transport.send0(Transport.java:254)
at javax.mail.Transport.send(Transport.java:124)
at org.wso2.carbon.event.output.adapter.email.EmailEventAdapter$EmailSender.run(EmailEventAdapter.java:306)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748) Caused by: java.net.SocketException: Connection timed out (Read failed)
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
at java.net.SocketInputStream.read(SocketInputStream.java:171)
at java.net.SocketInputStream.read(SocketInputStream.java:141)
at com.sun.mail.util.TraceInputStream.read(TraceInputStream.java:126)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:246)
at java.io.BufferedInputStream.read(BufferedInputStream.java:265)
at com.sun.mail.util.LineInputStream.readLine(LineInputStream.java:106)
at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:2440)
... 13 more
I already made changes in output-event-adapters.xml and axis2.xml for smtp details.
Any help on this?
output-event-adapters.xml configuration is as below:
noreply#xyz.com
noreply#xyz.com
ABC.XXX.XXX.XXX
25
true
false
8
100
20000
10000

Answer 1

It seems like it is blocked by google. Refer to this doc
If you are using Gmail account you have to on "Allow less secure apps"
in your account.
For more info refer this