Help Center

Fixing the 5.7.1. [ESR] error

The MailChannels abuse team may manually block a sender in your system when the sender is:

  • sending spam;
  • sending high volumes of suspicious bulk email;
  • generating complaints; or,
  • attempting to send to a large numbers of invalid recipients.

For Service Providers

This usually means that we did not find a authenticated user header in the mails and hence the system placed some aggressive policies against the account. Ensure there is no misconfiguration of your MTA that is preventing the addition of the headers.

Secure your account against compromise by spammers:

  • Change your password. Ensure your new password has a minimum length of eight characters and uses a mixture of upper and lower case letters, numbers, and special characters.
  • Verify that your operating system is running with the latest security updates.
  • Update your anti-virus software and conduct a full scan of your system to ensure that a spammer has not installed spam-sending malware on your computer.


For End Users

Contact your email service provider for assistance.

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