是否已使用调试模式尝试排错？
是
问题描述：
使用阿里云邮箱smtp后 邮件正常发送 前端显示错误
报错内容：
POST https://flac.cool/register
<br />
<b>Warning</b>: scandir(/www/wwwroot/flac.cool/vendor/fof/pretty-mail/src/../../../public/assets/): failed to open dir: No such file or directory in <b>/www/wwwroot/flac.cool/vendor/fof/pretty-mail/src/Mailer.php</b> on line <b>44</b><br />
<br />
<b>Warning</b>: scandir(): (errno 2): No such file or directory in <b>/www/wwwroot/flac.cool/vendor/fof/pretty-mail/src/Mailer.php</b> on line <b>44</b><br />
<br />
<b>Warning</b>: preg_grep() expects parameter 2 to be array, bool given in <b>/www/wwwroot/flac.cool/vendor/fof/pretty-mail/src/Mailer.php</b> on line <b>44</b><br />
<br />
<b>Fatal error</b>: Uncaught Laminas\HttpHandlerRunner\Exception\EmitterException: Output has been emitted previously; cannot emit response in /www/wwwroot/flac.cool/vendor/laminas/laminas-httphandlerrunner/src/Exception/EmitterException.php:24
Stack trace:
#0 /www/wwwroot/flac.cool/vendor/laminas/laminas-httphandlerrunner/src/Emitter/SapiEmitterTrait.php(40): Laminas\HttpHandlerRunner\Exception\EmitterException::forOutputSent()
#1 /www/wwwroot/flac.cool/vendor/laminas/laminas-httphandlerrunner/src/Emitter/SapiEmitter.php(27): Laminas\HttpHandlerRunner\Emitter\SapiEmitter->assertNoPreviousOutput()
#2 /www/wwwroot/flac.cool/vendor/laminas/laminas-httphandlerrunner/src/RequestHandlerRunner.php(98): Laminas\HttpHandlerRunner\Emitter\SapiEmitter->emit()
#3 /www/wwwroot/flac.cool/vendor/flarum/core/src/Http/Server.php(42): Laminas\HttpHandlerRunner\RequestHandlerRunner->run()
#4 /www/wwwroot/flac.cool/public/index.php(26): Flarum\Http\Server->listen()
#5 {main}
thrown in <b>/www/wwwroot/flac.cool/vendor/laminas/laminas-httphandlerrunner/src/Exception/EmitterException.php</b> on line <b>24</b><br />
已尝试的解决办法：
更换端口为25
网址：
https://flac.cool/