A large number of factors influence the successful delivery of emails. On rare occasions that an email does not reach one or more of the intended recipients, mail servers may provide error responses to indicate the nature of the error. These can be due to issues such as an incorrect domain, an invalid email address, or problems with server connectivity

There are several basic checks to be done when emails are not delivering to the customers from Freshdesk, including:

  • Check if the recipient's email address is correct and not misspelled.
  • Check if the email server is not down or experiencing any issues.
  • Check if the email is not landing in the spam or junk folder of the recipient. Certain keywords, excessive use of capital letters, excessive use of exclamation marks, or suspicious attachments, attachment size or file type limitations can raise red flags and cause the email to be marked as spam.
  • Check if the email settings such as DKIM in Freshdesk are configured properly if email set up is configured using Freshdesk mail server. Proper email authentication helps establish the sender's legitimacy and improves deliverability. Lack of authentication, such as not having SPF (Sender Policy Framework) or DKIM (DomainKeys Identified Mail) records set up correctly, can lead to emails being flagged as spam.
  • Check if the email is not getting filtered by any ticket automation or triggers in Freshdesk.
  • Check if your IP is blacklisted

Troubleshooting steps if your IP is backlisted

If you discover that your IP address is listed in blacklists, it indicates that your IP has been identified as a potential source of spam or malicious activity. Being blacklisted can negatively impact your email deliverability and online reputation. Here are some steps you can take to address the issue:

  • Verify the blacklist: Start by confirming that your IP address is indeed listed in the blacklists. You can use online tools like MXToolbox or Spamhaus to check blacklists.
  • Identify the cause: Determine why your IP address ended up on the blacklist. Possible reasons could include sending unsolicited emails, having compromised systems on your network, or being part of a shared hosting environment where other users are engaging in spammy activities.
Once you identify the cause, take appropriate actions to resolve it. Some common steps include:
  • Scan your network: Run security scans on your network to identify and resolve any compromised systems or malware infections.
  • Check email practices: Review your email sending practices to ensure compliance with best practices and anti-spam policies. Avoid sending unsolicited emails and make sure your recipients have opted in to receive your messages.
  • Secure your systems: Implement security measures such as strong passwords, firewalls, and up-to-date software to prevent unauthorized access and reduce the risk of being compromised.
  • Check for email authentication: Implement email authentication mechanisms like SPF, DKIM, and DMARC to verify your email's authenticity and reduce the chances of being flagged as spam.
  • Remove malicious content: If your website or server is hosting any malicious content, remove it promptly to prevent further issues.
  • Request delisting: Once you have addressed the underlying issues, you can request delisting from the respective blacklists. Each blacklist will have its own delisting process, which typically involves submitting a request through their website or following their instructions. Provide all the necessary information and evidence to support your request for removal.
  • Monitor and maintain good practices: Regularly monitor your IP reputation and email deliverability to ensure you stay off blacklists. Maintain good email sending practices, keep your systems secure, and promptly address any issues that arise.

Remember, it's important to take proactive measures to prevent blacklisting in the first place by following best practices and maintaining a clean and secure network.

Tracking undelivered messages

To track the mails failed to deliver, Freshdesk’s 'Email Delivery Failure Notification' feature sends notifications to corresponding agents to take corrective actions when replies or forwards do not reach the recipients. Further, these errors are visible as a part of the ticket conversation and also in the ticket activities view.


Please follow the steps below to set up 'Email Delivery Failure Notification' in your Freshdesk account.

  1. Login to your Freshdesk account as an administrator.

  2. Navigate to Admin. Under Workflows, click on Automations.

  3. Select Tickets. Under the Ticket updates tab, click on New Rule.

  4. Select the System option under the When an action performed by section.

  5. Under the Involves any of these events section, choose 'Mail sent to requester address failed' or 'Mail sent to cc or forward address failed' option as per your requirement.

    Set up email delivery failure notification in Freshdesk
  1. Select appropriate options for Ticket properties and Actions sections, then click on Preview and Save.

  2. Check for the rule summary and click on Save and Enable.

You can also make use of the curated tickets list view by navigating to Tickets > Ticket views > All undelivered messages to filter such tickets.


If the issue persists, please get in touch with support@freshdesk.com, and one of our agents will assist you further.