Mail from an NME Migrated user in an environment using CMN is delivered with a non-routable incorrect Notes style sender address. An example format for this bad address is:
Firstname_Surname%notesdomain@test.local
In certain environments this was found to specifically effect mails from Blackberry Device users or Notes Applications that generate emails.
Sometimes emails from BlackBerry Devices and non-Notes clients are missing a Notes field called INETFROM. Without this field and if Internet Address Lookup is not configured in the Global Domain document then the Domino Server will attempt to build the sender's address according to to the Domino Global Domain Document's Conversions Tab.
1- Check all Domino Global Domain Documents within the Domino Directory to ensure that Internet Address lookup is enabled
2- Verify that Notes Person records are configured with an Internet Address