Report on non-delivery to Yandex

If you sent an email to a Yandex mailbox and it didn't arrive, you will receive a non-delivery report from the “Mailer-Daemon” service.

The reason for why the email was not received will be indicated in the automatic report. How to find and interpret the error:

  1. Find the phrase Diagnostic Code. You will see the error code to the right of it.
  2. Find this code in the table below.
    Tip. For quick search in the table, use Ctrl+F for Windows and Cmd+F for macOS.
Error code Reason and solution

Bad recipient address syntax

Bad address mailbox syntax

No correct recipients

No such user

Recipient address rejected: need fully-qualified address

The email was sent to a non-existing address.

Make sure the recipient's address does not include extra punctuation marks, spaces, or quotation marks. Confirm the recipient's email address and resend the message.

Message rejected under suspicion of SPAM

Client host [IP_host] blocked using spamsource.mail.yandex.net; see...

Blocked by spam statistics — see...

The email seems to be spam.

If only spam is coming from your mailbox, the Yandex mail server will block receipt of messages from it for 24 hours.

Note. If you are sending legitimate messages to your website users or subscribers, please read Yandex requirements for honest mailing lists.

Policy rejection on the target address

The recipient's account has been blocked due to User Agreement violations.

Try contacting the recipient by another method and report the problem.

If you are the owner of the address to which the message has been sent, you can unblock it yourself. Fill in accurate information about yourself on the Personal information page and you will be unblocked after a while. If you have provided accurate information but weren't unblocked, please contact our support team via the feedback form at the bottom of the page.

Mailbox size exceeded

Mailbox size limit exceeded

Message infected by virus

The recipient's mailbox is full. This usually happens because the recipient does not use their mailbox often and their mailbox is full.

Try contacting the recipient by another method and report the problem. The recipient will have to log into Yandex.Mail via the web interface to be able to receive emails again.

Error: message file too big

Message size exceeds fixed limit

The attached file is too big. The Yandex email server cannot accept your attached file due to size restrictions. The maximum size of messages with attachments that can be sent to Yandex mailboxes is 30 MB.

Upload your attachment to a file storage service (such as Yandex.Disk) and include a link to it in your message.

Error: timeout exceeded

The recipient's email server is not responding. The recipient's email server took too long to respond and the Yandex email server disconnected and aborted the email delivery.

Try contacting the recipient by another method and report the problem.

Error: too many connections

The Yandex mail server is overloaded because of numerous requests from other servers. This increases the load on the server and slows it down.

Try contacting the recipient by another method and report the problem.

Error: too many recipients

This message has too many recipients, i.e. more than 35 addresses in the To, Cc, and Bcc fields.

Edit the list of recipients and try again.