XF 2.1 ErrorException: [E_NOTICE] fwrite(): send of 6 bytes failed with errno=32 Broken pipe

[shanew]

Hello,

I got this error in Xenforo 2

Server error log
ErrorException: [E_NOTICE] fwrite(): send of 6 bytes failed with errno=32 Broken pipe src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/StreamBuffer.php:240
Generated by: Unknown account May 26, 2020 at 3:06 PM
Stack trace
#0 [internal function]: XF::handlePhpError(8, '[E_NOTICE] fwri...', '/home/myuser...', 240, Array)
#1 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/StreamBuffer.php(240): fwrite(Resource id #157, 'QUIT
')
#2 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/ByteStream/AbstractFilterableInputStream.php(173): Swift_Transport_StreamBuffer->_commit('QUIT
')
#3 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/ByteStream/AbstractFilterableInputStream.php(92): Swift_ByteStream_AbstractFilterableInputStream->_doWrite('QUIT
')
#4 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(276): Swift_ByteStream_AbstractFilterableInputStream->write('QUIT
')
#5 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/EsmtpTransport.php(270): Swift_Transport_AbstractSmtpTransport->executeCommand('QUIT
', Array, Array)
#6 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(216): Swift_Transport_EsmtpTransport->executeCommand('QUIT
', Array)
#7 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(495): Swift_Transport_AbstractSmtpTransport->stop()
#8 [internal function]: Swift_Transport_AbstractSmtpTransport->__destruct()
#9 {main}
Request state
array(4) {
["url"] => string(8) "/job.php"
["referrer"] => string(49) "https://www.mydomain.com/whats-new/posts/802/"
["_GET"] => array(0) {
}
["_POST"] => array(0) {
}
}

and same this error

ErrorException: [E_NOTICE] fwrite(): send of 35 bytes failed with errno=32 Broken pipe src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/StreamBuffer.php:240
Generated by: Unknown account May 26, 2020 at 2:55 PM
Stack trace
#0 [internal function]: XF::handlePhpError(8, '[E_NOTICE] fwri...', '/home/myuser...', 240, Array)
#1 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/StreamBuffer.php(240): fwrite(Resource id #157, 'MAIL FROM:<info...')
#2 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/ByteStream/AbstractFilterableInputStream.php(173): Swift_Transport_StreamBuffer->_commit('MAIL FROM:<info...')
#3 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/ByteStream/AbstractFilterableInputStream.php(92): Swift_ByteStream_AbstractFilterableInputStream->_doWrite('MAIL FROM:<info...')
#4 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(276): Swift_ByteStream_AbstractFilterableInputStream->write('MAIL FROM:<info...')
#5 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/EsmtpTransport.php(270): Swift_Transport_AbstractSmtpTransport->executeCommand('MAIL FROM:<info...', Array, Array)
#6 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/EsmtpTransport.php(346): Swift_Transport_EsmtpTransport->executeCommand('MAIL FROM:<info...', Array)
#7 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(416): Swift_Transport_EsmtpTransport->_doMailFromCommand('info@myemail...')
#8 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(444): Swift_Transport_AbstractSmtpTransport->_doMailTransaction(Object(Swift_Message), 'info@myemail...', Array, Array)
#9 src/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(176): Swift_Transport_AbstractSmtpTransport->_sendTo(Object(Swift_Message), 'info@myemail...', Array, Array)
#10 src/XF/Mail/Mailer.php(292): Swift_Transport_AbstractSmtpTransport->send(Object(Swift_Message), Array)
#11 src/XF/Mail/Queue.php(138): XF\Mail\Mailer->send(Object(Swift_Message), Object(Swift_SmtpTransport), Array)
#12 src/XF/Job/MailQueue.php(12): XF\Mail\Queue->run(G)
#13 src/XF/Job/Manager.php(253): XF\Job\MailQueue->run(G)
#14 src/XF/Job/Manager.php(195): XF\Job\Manager->runJobInternal(Array, G)
#15 src/XF/Job/Manager.php(79): XF\Job\Manager->runJobEntry(Array, G)
#16 job.php(42): XF\Job\Manager->runQueue(false, 8)
#17 {main}
Request state
array(4) {
["url"] => string(8) "/job.php"
["referrer"] => string(57) "https://www.mydomain.com/wp-login.php?action=register"
["_GET"] => array(0) {
}
["_POST"] => array(0) {
}
}


Where caused this error and how to fix it?

Thank you!