This is a known issue with unmanaged endpoint feature in Officescan XG SP1. The server is unable to establish connection with the agents.
Please apply Officescan XG SP1 Hotfix 5110 to address this issue. To get a copy of the Hotfix, submit a request to Trend Micro Technical Support. This Hotfix will be included in Officescan XG SP1 Critical Patch 5294.
Important: Hotfixes are downloadable code fixes for bugs or specific issues that occurred to specific customers. Hotfixes are meant to be interim solutions that will eventually be consolidated into a patch or service pack for your product. Trend Micro recommends applying patches or service packs instead of individual hot fixes whenever possible.