使用说明文档中的第一个例子来发送qq邮件，邮件成功发送，但终端提示发送失败

[liuzhenqiuyyds]

    message.Subject("This is my first mail with go-mail!")
message.SetBodyString(mail.TypeTextPlain, "Do you like this mail? I certainly do!")

client, err := mail.NewClient("smtp.qq.com",
	mail.WithSMTPAuth(mail.SMTPAuthPlain),
	mail.WithUsername("[email protected]"),
	mail.WithPassword("xxxxxxxxxx"),
	mail.WithDebugLog(),
)
if err != nil {
	log.Fatalf("failed to create mail client: %s", err)
}

if err := client.DialAndSend(message); err != nil {
	log.Fatalf("failed to send mail: %s", err)
}

2025/08/01 16:21:30 DEBUG: C --> S: MAIL FROM:[email protected] BODY=8BITMIME SMTPUTF8
2025/08/01 16:21:30 DEBUG: C <-- S: 250 OK
2025/08/01 16:21:30 DEBUG: C --> S: RCPT TO:[email protected]
2025/08/01 16:21:30 DEBUG: C <-- S: 250 OK
2025/08/01 16:21:30 DEBUG: C --> S: DATA
2025/08/01 16:21:30 DEBUG: C <-- S: 354 End data with ..
2025/08/01 16:21:30 DEBUG: C --> S: NOOP
2025/08/01 16:21:30 DEBUG: C <-- S: 0
2025/08/01 16:21:30 DEBUG: C --> S: QUIT
2025/08/01 16:21:30 DEBUG: C <-- S: 0
2025/08/01 16:21:30 failed to send mail: send failed: sending SMTP RESET command: not connected to SMTP server, affected message ID: nhuulcnS2LaZvPLvLEKm4p@DESKTOP-8I82M0T
exit status 1

[wneessen]

Hi @liuzhenqiuyyds,

the issue you are seeing is not a go-mail issue but is a common issue with the qq.com mail provider (and some other Chinese providers that use the same mail server software). Their mailserver does not conform with the SMTP RFC by sending binary junk before issuing the response to the "QUIT" command, which confuses go-mail which expects the server to respond with the RFC-compliant response.

This has been discussed already and a workaround has been provided here: #463 (comment)

There is also an open issue (#464) in which we will provide a method to catch these errors much better. It will likely be part of the next go-mail release.

[liuzhenqiuyyds]

好的，谢谢你的回答，这个错误使我困惑了很久