Overview
If you're experiencing issues with email forwarding in Kerio Connect, it may be due to the lack of Sender Rewriting Scheme (SRS) support. This problem typically arises when you transfer a lot of messages and the final recipient uses SPF verification configured to hard-reject. As a result, the forwarded email that appears to be coming from another server not listed in the SPF record gets rejected.
This also can happen when redirecting DMARC quarantine reports, and 3rd party email providers may suggest that you implement SRS in order to circumvent this behavior. The mail log may contain lines similar to the below:
09/May/2023 11:16:24] Sent: Queue-ID: 5eb674e6-00033aad, Recipient: <test@example.com>, Result: failed, Status: 5.3.2 550 You are not allowed to use the domain example.net as DATA From domain., Remote-Host: 5.5.5.5, Msg-Id: <002701d625e2$77e8a420$67b9ec60$@sample@example.net>
Solution
The issue you're experiencing is due to Kerio Connect not supporting SRS with forwarded emails. This is causing errors when the final recipient uses SPF verification and has it configured to hard-reject, resulting in the rejection of the forwarded email that appears to be coming from another server not listed in the SPF record.
Unfortunately, there is no setting available in Kerio Connect to enable SRS. Therefore, it's not possible to install or implement SRS in Kerio Connect.
Summary
Issues with email forwarding in Kerio Connect can occur due to the lack of SRS support. This problem is particularly prevalent when the final recipient uses SPF verification configured to hard-reject. Unfortunately, Kerio Connect does not support SRS, and there is no available setting to enable it.
FAQ
1. Can I install or implement SRS in Kerio Connect?
No, Kerio Connect does not support SRS, and there is no available setting to enable it.
2. Why are my forwarded emails getting rejected?
Your forwarded emails may be getting rejected if the final recipient uses SPF verification configured to hard-reject, and the email appears to be coming from another server not listed in the SPF record.
3. What is SRS and why is it important for email forwarding?
SRS, or Sender Rewriting Scheme, is a scheme for rewriting the envelope sender address of an email message in order to forward it. It's important for email forwarding because it helps prevent the email from being marked as spam or rejected by the recipient's email server.