------------------------------------------------- This is the final update on the issue.
We have maintained our monitoring and confirmed no further recurrences. The issue is now considered completely resolved. The incident occurred during the following timeframe:
- Around 14:52 to 18:24 on June 12, 2026 (JST)
We deeply apologize for any disruption this may have caused.
------------------------------------------------- This is an update on the ongoing issue.
As of now, no further false-positive RBL listings or email blocks have been observed, and the issue appears to be resolving. We will keep monitoring the system to prevent any recurrence.
We apologize for the disruption and thank you for your patience.
------------------------------------------------- We have confirmed an ongoing issue where certain emails routed through HENNGE Email DLP are being rejected at the destination. This is due to false-positive listings on RBLs such as Spamhaus.
Our system team is actively investigating and has already initiated the delisting process with the relevant RBLs.
If your message is blocked by this issue, you may receive a bounce message (NDR) containing the following error codes and keywords:
■ Error Code 500 series (Displayed in the message as "said: 550 ...")
■ Keywords - Spamhaus - Rejected - Blocked
Please note that receiving this notification indicates your email was not delivered. We apologize for the trouble, but please allow some time to pass before attempting to resend your email.
We apologize for the inconvenience and thank you for your cooperation.