官网地址 https://support.google.com/a/answer/3726730?hl=en
使用google邮箱需要了解的专业知识 https://support.google.com/a/answer/81126
我可以帮助您搭建邮件服务器，详情了解：《Mailwizz服务器搭建》
421, "4.3.0", Temporary System Problem. Try again later
421, "4.4.5", Server busy, try again later.
421, "4.7.0", IP not in whitelist for RCPT domain, closing connection.
421, "4.7.0", Our system has detected an unusual rate of unsolicited mail originating from your IP address. To protect our users from spam, mail sent from your IP address has been temporarily blocked. For more information, visit Prevent mail to Gmail users from being blocked or sent to spam.
421, "4.7.0", Temporary System Problem. Try again later.
421, "4.7.0", TLS required for RCPT domain, closing connection.
421, "4.7.0", Try again later, closing connection. This usually indicates a Denial of Service (DoS) for the SMTP relay at the HELO stage.
450, "4.2.1" The user you are trying to contact is receiving mail too quickly. Please resend your message at a later time. If the user is able to receive mail at that time, your message will be delivered. For more information, visit Limits for sending & getting mail.
450, "4.2.1", The user you are trying to contact is receiving mail at a rate that prevents additional messages from being delivered. Please resend your message at a later time. If the user is able to receive mail at that time, your message will be delivered. For more information, visit Limits for sending & getting mail.
450, "4.2.1", Peak SMTP relay limit exceeded for customer. This is a temporary error. For more information on SMTP relay limits, please contact your administrator or visit SMTP relay service error messages.
451, "4.3.0", Mail server temporarily rejected message.
451, "4.3.0", Multiple destination domains per transaction is unsupported. Please try again.
451, "4.4.2", Timeout - closing connection.
451, "4.5.0", SMTP protocol violation, visit RFC 2821.
452, "4.2.2", The email account that you tried to reach is over quota. Please direct the recipient to Clear Google Drive space & increase storage.
452, "4.5.3", Domain policy size per transaction exceeded, please try this recipient in a separate transaction.
This message means the email policy size (size of policies, number of policies, or both) for the recipient domain has been exceeded.
452, "4.5.3", Your message has too many recipients. For more information regarding Google's sending limits, visit Limits for sending & getting mail.
454, "4.5.0", SMTP protocol violation, no commands allowed to pipeline after STARTTLS, visit RFC 3207.
454, "4.7.0", Cannot authenticate due to temporary system problem. Try again later.
454, "5.5.1", STARTTLS may not be repeated.
501, "5.5.2", Cannot Decode response.
501, "5.5.4", HELO/EHLO argument is invalid. For more information, visit HELO/EHLO email error.
502, "5.5.1", Too many unrecognized commands, goodbye.
502, "5.5.1", Unimplemented command.
502, "5.5.1", Unrecognized command.
503, "5.5.1", "EHLO/HELO first.
503, "5.5.1", MAIL first.
503, "5.5.1", RCPT first.
503, "5.7.0", No identity changes permitted.
504, "5.7.4", Unrecognized Authentication Type.
530, "5.5.1", Authentication Required. For more information, visit Can't sign in to your Google Account.
530, "5.7.0", Must issue a STARTTLS command first.
535, "5.5.4", Optional Argument not permitted for that AUTH mode.
535, "5.7.1", Application-specific password required. For more information, visit Sign in using App Passwords.
535, "5.7.1", Please log in with your web browser and then try again. For more information, visit Check Gmail through other email platforms.
535, "5.7.1", Username and Password not accepted. For more information, visit Can't sign in to your Google Account.
550, "5.1.1", The email account that you tried to reach does not exist. Please try double-checking the recipient's email address for typos or unnecessary spaces. For more information, visit Fix bounced or rejected emails.
550, "5.2.1", The email account that you tried to reach is disabled.
550, "5.2.1", The user you are trying to contact is receiving mail at a rate that prevents additional messages from being delivered. For more information, visit Limits for sending & getting mail.
550, "5.4.5", Daily sending quota exceeded. For more information, visit Email sending limits.
550, "5.4.5", Daily SMTP relay limit exceeded for user. For more information on SMTP relay sending limits please contact your administrator or visit SMTP relay service error messages.
550, "5.7.0", Mail relay denied.
550, "5.7.0", Mail Sending denied. This error occurs if the sender account is disabled or not registered within your Google Workspace domain.
550, "5.7.1", Email quota exceeded.
550, "5.7.1", Invalid credentials for relay.
550, "5.7.1", Our system has detected an unusual rate of unsolicited mail originating from your IP address. To protect our users from spam, mail sent from your IP address has been blocked. Review Prevent mail to Gmail users from being blocked or sent to spam.
550, "5.7.1", Our system has detected that this message is likely unsolicited mail. To reduce the amount of spam sent to Gmail, this message has been blocked. For more information, visit Why has Gmail blocked my messages?
550, "5.7.1", The IP you're using to send mail is not authorized to send email directly to our servers. Please use the SMTP relay at your service provider instead. For more information, visit 'The IP you're using to send email is not authorized…'.
550, "5.7.1", The user or domain that you are sending to (or from) has a policy that prohibited the mail that you sent. Please contact your domain administrator for further details. For more information, visit Sorry, a policy is in place that prevents your message from being sent.
550, "5.7.1", Unauthenticated email is not accepted from this domain.
550, "5.7.1", Daily SMTP relay limit exceeded for customer. For more information on SMTP relay sending limits please contact your administrator or visit SMTP relay service error messages.
550, "5.7.26", " Unauthenticated email from domain-name is not accepted due to domain's DMARC policy. Please contact the administrator of domain-name domain. If this was a legitimate mail please visit Control unauthenticated mail from your domain to learn about the DMARC initiative. If the messages are valid and aren't spam, contact the administrator of the receiving mail server to determine why your outgoing messages don't pass authentication checks.
550, "5.7.26", "This message does not have authentication information or fails to pass authentication checks (SPF or DKIM). To best protect our users from spam, the message has been blocked. Please visit Prevent mail to Gmail users from being blocked or sent to spam for more information."
550, "5.7.26", "This message fails to pass SPF checks for an SPF record with a hard fail policy (-all). To best protect our users from spam and phishing, the message has been blocked. Please visit Prevent mail to Gmail users from being blocked or sent to spam for more information."
552, "5.2.2", The email account that you tried to reach is over quota.
552, "5.2.3", Your message exceeded Google's message size limits. For more information, visit Send attachments with your Gmail message.
553, "5.1.2", We weren't able to find the recipient domain. Please check for any spelling errors, and make sure you didn't enter any spaces, periods, or other punctuation after the recipient's email address.
554, "5.6.0", Mail message is malformed. Not accepted.
554, "5.6.0", Message exceeded 50 hops, this may indicate a mail loop.
554, "5.7.0", Too Many Unauthenticated commands.
555, "5.5.2", Syntax error.
以下为中文翻译版：
421, "4.3.0", 临时系统问题。请稍后重试
421, "4.4.5", 服务器繁忙，请稍后重试。
421, "4.7.0", IP 未列入 RCPT 网域的白名单，正在断开连接。
421, "4.7.0", 我们的系统检测到您的 IP 地址发出了数量庞大、来路不明的邮件。为保护我们的用户免受垃圾邮件的骚扰，系统暂时屏蔽了从您 IP 地址发送的邮件。有关详情，请参阅防止发送给 Gmail 用户的邮件遭到屏蔽或被列为垃圾邮件。
421, "4.7.0", 临时系统问题。请稍后重试。
421, "4.7.0", RCPT 网域需要 TLS，正在断开连接。
421, "4.7.0", 请稍后重试，正在断开连接。这通常表示 HELO 阶段的 SMTP 中继遇到拒绝服务攻击 (DoS)。
450, "4.2.1", 您尝试联系的用户目前接收邮件过于频繁。请稍后重发您的邮件。如果届时用户可以接收邮件，则系统将递送您的邮件。有关详情，请参阅收发邮件的限制。
450, "4.2.1", 您尝试联系的用户目前接收邮件过于频繁，因此系统无法递送更多邮件。请稍后重发您的邮件。如果届时用户可以接收邮件，则系统将递送您的邮件。有关详情，请参阅收发邮件的限制。
450, "4.2.1", 客户的最高 SMTP 中继量超出限制。此错误是暂时性的。有关 SMTP 中继限制的详细信息，请与您的管理员联系或参阅 SMTP 中继服务错误消息。
451, "4.3.0", 邮件服务器暂时拒绝接收邮件。
451, "4.3.0", 单次邮件操作不可包含多个目标网域。请重试。
451, "4.4.2", 超时 - 正在断开连接。
451, "4.5.0", 违反 SMTP 协议，请参阅 RFC 2821。
452, "4.2.2", 您尝试通信的收件人的电子邮件帐号已超出配额。请引导收件人清理 Google 云端硬盘空间和增加存储空间。
452, "4.5.3", 已超过每次操作所允许的网域政策大小，请单独向此收件人发送邮件。
收到此邮件，则表示收件人网域已超出电子邮件政策大小（政策大小和/或政策数量）上限。
452, "4.5.3", 您的邮件包含的收件人过多。要了解有关 Google 发送限制的详细信息，请参阅收发邮件的限制。
454, "4.5.0", 违反 SMTP 协议，不允许在 STARTTLS 之后传输任何命令，请参阅 RFC 3207。
454, "4.7.0", 临时系统问题导致无法进行身份验证。请稍后重试。
454, "5.5.1", 不可重复执行 STARTTLS。
501, "5.5.2", 无法对响应进行解码。
501, "5.5.4", HELO/EHLO 参数无效。详情请参阅 HELO/EHLO 电子邮件错误。
502, "5.5.1", 无法识别的命令过多，正在断开连接。
502, "5.5.1", 尚未实现命令。
502, "5.5.1", 无法识别命令。
503, "5.5.1", "先执行 EHLO/HELO。
503, "5.5.1", 先执行 MAIL。
503, "5.5.1", 先执行 RCPT。
503, "5.7.0", 不允许更改身份。
504, "5.7.4", 无法识别身份验证类型。
530, "5.5.1", 需要进行身份验证。有关详情，请参阅无法登录您的 Google 帐号。
530, "5.7.0", 必须先发出 STARTTLS 命令。
535, "5.5.4", 该身份验证模式不允许使用可选参数。
535, "5.7.1", 需要应用专用密码。有关详情，请参阅使用应用专用密码登录。
535, "5.7.1", 请使用网络浏览器进行登录，然后重试。有关详情，请参阅通过其他电子邮件平台查看 Gmail。
535, "5.7.1", 系统不接受用户名和密码。有关详情，请参阅无法登录您的 Google 帐号。
550, "5.1.1", 您尝试向其发送邮件的电子邮件帐号不存在。请再次仔细检查收件人的电子邮件地址，确保没有拼写错误或多余空格。有关详情，请参阅解决电子邮件被退回或遭拒的问题。
550, "5.2.1", 您尝试通信的收件人的电子邮件帐号已被停用。
550, "5.2.1", 您尝试联系的用户目前接收邮件过于频繁，因此系统无法递送更多邮件。有关详情，请参阅收发邮件的限制。
550, "5.4.5", 已超过每日发送配额。有关详情，请参阅电子邮件发送限制。
550, "5.4.5", 用户的每日 SMTP 中继量超出限制。有关 SMTP 中继发送上限的详细信息，请与您的管理员联系或参阅 SMTP 中继服务错误消息。
550, "5.7.0", 已拒绝邮件中继。
550, "5.7.0", 已拒绝发送邮件。如果发件人的帐号已停用或未在您的 Google Workspace 网域中注册，就会发生此错误。
550, "5.7.1", 已超过电子邮件配额。
550, "5.7.1", 中继凭据无效。
550, "5.7.1", 我们的系统检测到您的 IP 地址发出了数量庞大、来路不明的邮件。为保护我们的用户免受垃圾邮件的骚扰，系统屏蔽了从您的 IP 地址发出的邮件。有关详情，请参阅防止发送给 Gmail 用户的邮件遭到屏蔽或被列为垃圾邮件。
550, "5.7.1", 我们的系统检测出此邮件可能属于来路不明的邮件。为减少发送至 Gmail 的垃圾邮件数量，系统已屏蔽此邮件。有关详情，请参阅 Gmail 为什么阻止了我的邮件？
550, "5.7.1", 您用于发送邮件的 IP 无权直接向我们的服务器发送电子邮件。请改用服务提供商的 SMTP 中继服务。有关详情，请参阅"The IP you're using to send email is not authorized…"（您用于发送电子邮件的 IP 未经授权…）
550, "5.7.1", 您发送邮件的目标（或来源）用户或网域设置了一项政策，该政策会阻止您发送的邮件。请向您的网域管理员了解详细信息。有关详情，请参阅很抱歉，由于政策限制，目前系统无法发送您的邮件。
550, "5.7.1", 此网域拒绝接收未经身份验证的电子邮件。
550, "5.7.1", 客户的每日 SMTP 中继量超出限制。有关 SMTP 中继发送上限的详细信息，请与您的管理员联系或参阅 SMTP 中继服务错误消息。
550, "5.7.26", 由于网域的 DMARC 政策，不接受来自 <域名> 的未经身份验证的电子邮件。请与 <域名> 网域的管理员联系。如果这是正常邮件，请访问控制来自您网域的未经身份验证的邮件，了解 DMARC 计划。如果邮件有效且不是垃圾邮件，请与邮件接收服务器的管理员联系，以确定外发邮件无法通过身份验证检查的原因。
550, "5.7.26",“此邮件没有身份验证信息，或未能通过身份验证检查（SPF 或 DKIM）。为保护我们的用户免受垃圾邮件的骚扰，此邮件已被屏蔽。请访问防止发送给 Gmail 用户的邮件遭到屏蔽或被列为垃圾邮件以了解详情。”
550, "5.7.26",“此邮件未能通过 SPF 检查，SPF 记录包含硬性故障政策 (-all)。为保护我们的用户免受垃圾邮件和钓鱼邮件的骚扰，此邮件已被屏蔽。请访问防止发送给 Gmail 用户的邮件遭到屏蔽或被列为垃圾邮件以了解详情。”
552, "5.2.2", 您尝试向其发送邮件的电子邮件帐号已超出配额。
552, "5.2.3", 您的邮件超出了 Google 的邮件大小限制。有关详情，请参阅通过 Gmail 邮件发送附件。
553, "5.1.2", 我们无法找到收件人的域名。请检查是否存在拼写错误，并确保您未在收件人电子邮件地址末尾输入空格、句号或其他标点符号。
554, "5.6.0", 邮件格式错误。未接受。
554, "5.6.0", 邮件超过 50 个跃点，这可能是由于邮件递送循环。
554, "5.7.0", 未经身份验证的命令过多。
555, "5.5.2", 语法错误。
下面是腾讯邮箱错误汇总中文翻译
550 Mailbox unavailable or access denied： 收件箱不可用或拒绝访问。通常表示邮箱地址不存在、已被禁用或被配置为拒绝接收邮件。
550 Mail content denied： 邮件内容被拒绝。通常由于邮件内容包含垃圾邮件或病毒特征，或触发了接收方邮件服务器的安全规则。
550 SPF check failed： SPF 检查失败。表示发件人的 SPF 记录未能验证，无法证明邮件来自授权的服务器。
550 Mail is rejected by recipients： 邮件被收件人拒绝。通常由于收件人设置了过滤规则或黑名单。
550 Domain may not exist or DNS check failed： 域名可能不存在或 DNS 检查失败。表示发件人邮件地址中的域名可能不存在或其 DNS 配置有问题。
550 DMARC check failed： DMARC 检查失败。表示邮件未能通过 DMARC 验证，可能存在欺骗或伪造的风险。
550 Spam is embedded in the email： 邮件中嵌入了垃圾邮件。通常表示邮件内容包含垃圾邮件特征或被识别为垃圾邮件。
550 Mime from domain is a local domain： 邮件头中的 Mime From 域是本地域。通常表示发件人试图伪造邮件来源。
550 DKIM check failed： DKIM 检查失败。表示邮件未能通过 DKIM 验证，无法证明邮件内容的完整性。
550 Sender domain is a local domain： 发件人域是本地域。通常表示发件人试图伪造邮件来源。
501 Bad address syntax： 邮件地址语法错误。通常表示邮件地址格式不正确。
552 Message too large： 邮件太大。表示邮件大小超过了接收方邮件服务器的限制。
550 Sender frequency limited： 发件人频率受限。表示发件人近期发送邮件过于频繁，被临时限制发送。
550 Connection frequency limited： 连接频率受限。表示发件人邮件服务器连接接收方邮件服务器的频率过高，被临时限制连接。
450 Too many concurrent connections from your IP： 同一 IP 地址的并发连接过多。表示发件人 IP 地址发起的并发连接数超过了限制。
The “From" header is missing or invalid： “From" 头部缺失或无效。表示邮件缺少或包含无效的“From" 头部，无法确定发件人信息。
550 Invalid sender address： 发件人地址无效。通常表示发件人地址不存在或格式不正确。
550 Suspected spam： 疑似垃圾邮件。表示邮件被判定为疑似垃圾邮件。
Multiple “From" headers found： 发现多个“From" 头部。表示邮件包含多个“From" 头部，可能存在伪造邮件来源的嫌疑。
550 Invalid “From" found in header： 头部中的“From" 无效。表示邮件头部中的“From" 地址不存在或格式不正确。
550 Suspected spam ip： 疑似垃圾邮件 IP。表示发件人 IP 地址有发送垃圾邮件的嫌疑。
550 Ip frequency limited： IP 频率受限。表示发件人 IP 地址近期发送邮件过于频繁，被临时限制发送。
550 Suspected spam sender： 疑似垃圾邮件发送者。表示发件人有发送垃圾邮件的嫌疑。
550 Suspected bounce attacks： 疑似退信攻击。表示接收方邮件服务器怀疑发件人试图进行退信攻击。
550 Domain frequency limited 表示发件人域名的发信频率超过了接收方邮件服务器的限制。通常，接收方邮件服务器会对发件人域名进行发信频率限制，以防止垃圾邮件或其他恶意邮件泛滥。