Email error 550 5.7.1 'Unable to relay a message' or 'Client was not authenticated' is an error code that prevents sending emails by either server or client. The meaning behind this particular set of numbers depends on what attributes it's related to—i.e., number 550 means "550 unable...
7. Server Error 550 or 550 Blocked Error This error pops up across the computer when the recipient hosting server blocks emails. The email is redirected back to the sender as per the instructions of the SMTP error code. 8. Error 550 in Outlook Associated with a 550 Authentication error, th...
550 5.7.64 TenantAttribution; Relay Access Denied SMTP Senders receive a non-delivery report (NDR) that contains this error code. Or, you see the error logged in IIS SMTP logs or in Send connector logs.Additionally, if you enabled CAPI2 operational logging in Event Viewer, the following ...
Hard bounces (500 Series): These indicate permanent problems with email delivery. Examples include non-existent email addresses (code 550), unauthorized users (code 551), or incorrect domain names (code 554). Hard bounces require immediate action, such as verifying the recipient's email address o...
When sending email to a user on the Symantec Email Security.cloud service, the message is rejected. The sender receives a non-delivery email with a 500 series error code indicating that the recipient is invalid. <username@example.com>: 550-Invalid recipient <username@example.com> ...
The NDR contains the following error code: 550 5.1.10 RESOLVER.ADR.RecipientNotFound; Recipient not found by SMTP address lookup Cause This problem occurs if the user was created in Microsoft 365. In this scenario, the on-premises Exchange environment has no object to reference for the user....
Learn how to fix email issues for error code 5.7.1 (and also 5.7.0 to 5.7.999) in Exchange Online (the recipient is configured to reject email from the sender).
Ensure that the recipient's email address and domain are accurate. Reach out to the recipient and inquire whether they require TLS for email delivery. Contact your ESP’s support team for assistance in configuring TLS. Error code 550 5.7.1 - Blocked, Marked as spam, Authentication Example: Em...
The NDR contains the following error code: 550 5.1.10 RESOLVER.ADR.RecipientNotFound; Recipient not found by SMTP address lookup Cause This problem occurs if the user was created in Microsoft 365. In this scenario, the on-premises Exchange environment has no object to reference for the ...
错误消息:550 RC:LD你想达到的电子邮件帐户,并没有存在。 翻译结果2复制译文编辑译文朗读译文返回顶部 错误消息: 550 RC:LD 的电子邮件帐户,您试图达成并不存在。 翻译结果3复制译文编辑译文朗读译文返回顶部 错误消息: 550 RC:LD 的电子邮件帐户,您试图达成并不存在。