If ScanMail is integrated with Virtual Analyzer, then Trend Micro strongly recommends deploying the same version of ScanMail throughout all Exchange servers in the organization.

The latest version of ScanMail can use the updated scan logic and security enhancements for email messages than the older one. Therefore, it is possible that the older version of ScanMail may not recognize the messages routed from the newer version after they are analyzed by Virtual Analyzer.