Troubleshooting transport or DLP rules is sometime a tricky thing.
Exchange administrator can now use a new cmdlet – Test-Message – to investigate why transport rule did not trigger or work as expected.
Test-Message –Sender <sender email address – can be external> –Recipients <recipient email address – can be external> –SendReportTo <report recipient email address> –TransportRules
After few minutes, the report is sent; it shows all rules implemented with corresponding evaluation condition state