ERS is an email filtering service that protects your business against spam and inappropriate content before they reach your network. Trend Micro supplies the hardware, software, and messaging expertise to cleanse your email. The cleaned mail stream is sent directly to your mail server for final delivery to your end users.

To know more about ERS, refer to the ERS Admin Guide.

Messages are blocked and cannot be received by the recipients because the sender's IP address has been added in the ERS database. Recipients using ERS to block spam messages will not receive messages.

The sender's IP address is added to the ERS database because spam messages may have been sent from that IP address.

If your MTA or mail server is an open mail relay, there is a possibility that the MTA was used by spammers.

Before you remove an IP address from the database, you need to first disable open mail relay on your MTA.

To remove the IP address, refer to the article: Removing valid IP addresses

that are blocked by Hosted Email Security (HES) from the Email Reputation Services (ERS) database

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