Overview
This topic describes how to troubleshoot the failure to send emails.
Detailed Information
The following are the corresponding troubleshooting items:
1. When sending the email, please fill in the complete and correct recipient address (the general email address format is "prefix@domain name", and no spaces or other special characters are allowed).
2. Please check the size of the attachment. The size of the ordinary attachment should be less than 50MB, and the size of a single large attachment should not exceed 4GB. For more information about the limits on common and large attachment, please check The Differences between Attachment and Large Attachment.
3. The number of group sending recipients on the Webmail cannot exceed 300, and the group sending addresses are separated by semicolons in English.
4. The email cannot be sent by the third-party email client. Please check the client settings by referring to the How to Configure Alibaba Mail Accounts on the Third-party Email Client according to the different email clients.
5. If you receive a return email after sending the email, you can first open the system to view the reason for returning the email, and then perform corresponding operations according to the specific reason. For the reason of returning the email, please refer to Common Bounce Notification and Solutions.
6. Whether the email account sent a large number of emails in a short period of time, which exceeds the sending limit of the day. Please control the sending frequency and quantity, and try to send the email in the next day. Please refer to the Sending Frequency or Quantity Exceeding the Alibaba Mail Limit for more information.
7. The account has not been logged in for a long time. In order to protect the security of the account, the system will automatically turn on the external sending restriction. When sending the letter, a "system error, unable to send" error will be reported. Please contact the mailbox administrator to turn on the External Send function again.
8. If it still cannot be sent after all the above methods are checked, it may be caused by unstable network or server upgrading (please refer to the announcement page). It is recommended that you send it later.