After performing the object merge and mailbox enabling of an AD user that once had forwarding set on it, the autocomplete will cause a non delivery of email because the Outlook autocomplete has stored the forwarding address information, and not the new Exchange mailbox for that user. This autocomplete must be cleared.
By default, the migration does not clear this cached autocomplete address information.
You can have NME clear the autocomplete information on a user's mailbox when you migrate their email. Moving forward, adding this INI setting will prevent this occurance on any future existing migrations.
In the Migration Manager, go to the Edit |Global Default Settings and add:
Here's an explanation of what it does:
Type: boolean. Optional. Default: 0
Determines whether the Wizard will delete the IPM.Configuration.Autocompletion
message from the Inbox at the end of its data migration run. The AutoCompletion
configuration message holds the cache of recently mailed-to users, but
will cause errors in Outlook if the auto-completion lookup tables are corrupted—
in which case Outlook will mistakenly tell users that valid addresses are invalid.
The feature is off by default (DeleteAutocompleteMessages=0), but can be
enabled by setting: