Failed to authenticate on SMTP server with username \"username@mailserver.xx\" using 0 possible authenticators.

[PhillerEU]

PHP version: 8.x
FreeScout version: 1.8.158
Database: MySQL
Are you using CloudFlare: Yes
Are you using non-official modules: Yes

We keep getting below send errors on two mailboxes out of all our 15.
Tried switching to own mail server so we could rule out O365 as the issue. That didn't help.
We can send testmails from the testfunction in freescout, but no actual conversations get sent.
I can connect and send from the mailserver just fine from another vendor.
Tried to change from 587 TLS to 465 SSL, no difference.

Hopefully someone has dealt with this and can help.

(username and server redacted)

[2024-12-01 10:20:27] production.ERROR: Failed to authenticate on SMTP server with username "username@mailserver.net" using 0 possible authenticators. {"exception":"[object] (Swift_TransportException(code: 0): Failed to authenticate on SMTP server with username "username@mailserver.net" using 0 possible authenticators. at /var/www/html/overrides/swiftmailer/swiftmailer/lib/classes/Swift/Transport/Esmtp/AuthHandler.php:191)
[stacktrace]
#0 /var/www/html/overrides/swiftmailer/swiftmailer/lib/classes/Swift/Transport/EsmtpTransport.php(371): Swift_Transport_Esmtp_AuthHandler->afterEhlo()
#1 /var/www/html/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(148): Swift_Transport_EsmtpTransport->doHeloCommand()
#2 /var/www/html/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Mailer.php(65): Swift_Transport_AbstractSmtpTransport->start()
#3 /var/www/html/vendor/laravel/framework/src/Illuminate/Mail/Mailer.php(451): Swift_Mailer->send()
#4 /var/www/html/vendor/laravel/framework/src/Illuminate/Mail/Mailer.php(235): Illuminate\Mail\Mailer->sendSwiftMessage()
#5 /var/www/html/vendor/laravel/framework/src/Illuminate/Mail/Mailable.php(125): Illuminate\Mail\Mailer->send()
#6 /var/www/html/vendor/laravel/framework/src/Illuminate/Mail/Mailer.php(250): Illuminate\Mail\Mailable->send()
#7 /var/www/html/vendor/laravel/framework/src/Illuminate/Mail/Mailer.php(205): Illuminate\Mail\Mailer->sendMailable()
#8 /var/www/html/vendor/laravel/framework/src/Illuminate/Mail/PendingMail.php(99): Illuminate\Mail\Mailer->send()
#9 /var/www/html/app/Jobs/SendAutoReply.php(82): Illuminate\Mail\PendingMail->send()
#10 [internal function]: App\Jobs\SendAutoReply->handle()
#11 /var/www/html/overrides/laravel/framework/src/Illuminate/Container/BoundMethod.php(29): call_user_func_array()
#12 /var/www/html/overrides/laravel/framework/src/Illuminate/Container/BoundMethod.php(87): Illuminate\Container\BoundMethod::Illuminate\Container\{closure}()
#13 /var/www/html/overrides/laravel/framework/src/Illuminate/Container/BoundMethod.php(31): Illuminate\Container\BoundMethod::callBoundMethod()
#14 /var/www/html/overrides/laravel/framework/src/Illuminate/Container/Container.php(549): Illuminate\Container\BoundMethod::call()
#15 /var/www/html/vendor/laravel/framework/src/Illuminate/Bus/Dispatcher.php(94): Illuminate\Container\Container->call()
#16 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(114): Illuminate\Bus\Dispatcher->Illuminate\Bus\{closure}()
#17 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(102): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#18 /var/www/html/vendor/laravel/framework/src/Illuminate/Bus/Dispatcher.php(98): Illuminate\Pipeline\Pipeline->then()
#19 /var/www/html/vendor/laravel/framework/src/Illuminate/Queue/CallQueuedHandler.php(49): Illuminate\Bus\Dispatcher->dispatchNow()
#20 /var/www/html/vendor/laravel/framework/src/Illuminate/Queue/Jobs/Job.php(76): Illuminate\Queue\CallQueuedHandler->call()
#21 /var/www/html/vendor/laravel/framework/src/Illuminate/Queue/Worker.php(320): Illuminate\Queue\Jobs\Job->fire()
#22 /var/www/html/vendor/laravel/framework/src/Illuminate/Queue/Worker.php(270): Illuminate\Queue\Worker->process()
#23 /var/www/html/vendor/laravel/framework/src/Illuminate/Queue/Worker.php(114): Illuminate\Queue\Worker->runJob()
#24 /var/www/html/vendor/laravel/framework/src/Illuminate/Queue/Console/WorkCommand.php(101): Illuminate\Queue\Worker->daemon()
#25 /var/www/html/vendor/laravel/framework/src/Illuminate/Queue/Console/WorkCommand.php(85): Illuminate\Queue\Console\WorkCommand->runWorker()
#26 [internal function]: Illuminate\Queue\Console\WorkCommand->handle()
#27 /var/www/html/overrides/laravel/framework/src/Illuminate/Container/BoundMethod.php(29): call_user_func_array()
#28 /var/www/html/overrides/laravel/framework/src/Illuminate/Container/BoundMethod.php(87): Illuminate\Container\BoundMethod::Illuminate\Container\{closure}()
#29 /var/www/html/overrides/laravel/framework/src/Illuminate/Container/BoundMethod.php(31): Illuminate\Container\BoundMethod::callBoundMethod()
#30 /var/www/html/overrides/laravel/framework/src/Illuminate/Container/Container.php(549): Illuminate\Container\BoundMethod::call()
#31 /var/www/html/vendor/laravel/framework/src/Illuminate/Console/Command.php(183): Illuminate\Container\Container->call()
#32 /var/www/html/vendor/symfony/console/Command/Command.php(255): Illuminate\Console\Command->execute()
#33 /var/www/html/vendor/laravel/framework/src/Illuminate/Console/Command.php(170): Symfony\Component\Console\Command\Command->run()
#34 /var/www/html/vendor/symfony/console/Application.php(992): Illuminate\Console\Command->run()
#35 /var/www/html/vendor/symfony/console/Application.php(255): Symfony\Component\Console\Application->doRunCommand()
#36 /var/www/html/vendor/symfony/console/Application.php(148): Symfony\Component\Console\Application->doRun()
#37 /var/www/html/vendor/laravel/framework/src/Illuminate/Console/Application.php(88): Symfony\Component\Console\Application->run()
#38 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Console/Kernel.php(121): Illuminate\Console\Application->run()
#39 /var/www/html/artisan(62): Illuminate\Foundation\Console\Kernel->handle()
#40 {main}
"}

[PhillerEU]

Sent a message from both mailboxes yesterday afternoon, they just arrived this morning. Any idea of what could cause that?

[freescout-help]

Unfortunately no clues.

All the advices are here: https://github.com/freescout-help-desk/freescout/wiki/Sending-Issues

[JesperLK-Witt]

We are still have problem with this, have checked everything in https://github.com/freescout-help-desk/freescout/wiki/Sending-Issues.
Its one of the latest releases that have changed it, if you ask me ;-)
Sometime it can answer the costumer, other times it fails with the "Send error. Failed to authenticate on SMTP server with username "***" using 0 possible authenticators.. Message-ID: reply-89977-ecf12c9e3aefdb7d@domain.com"
Tested with the same costumer and another costumer. Same issues - sometimes it works other times not!

Maybe someone wiser than us that can tell if it could be releated to this: 0280e4f

Hoping to find the solution soon so we can start answering out costumers again :-)
Jesper

[freescout-help]

Maybe someone wiser than us that can tell if it could be releated to this: 0280e4f

No. That issue has been fixed.