#4. Add X500 email addresses to the destination

In some cases following migration, end users may be unable to update events. When migrating auto-complete lists, there can be LegacyExchangeDN entries from source mailboxes. If end users directly use migrated auto-complete lists when sending emails, the emails may not be sent, and end users will get a non-delivery report (NDR).

The issues above can be resolved by adding the X500 email address to destination mailboxes. To add X500 email addresses to the destination, refer to for details.

*Note: You only need to add X500 email addresses to the destination in the current migration wave.