To resolve this, use the following parameter in the General Section of the Global Defaults INI
MsgRequireAnyFeature=<#>
Tells the Data Migration Wizard which types of messages to migrate, depending on the features of each message. The parameter value must be one of these single-digit numeric keywords:
0 (default): Migrate all items.
1: Migrate only items with embedded OLE objects.
2: Migrate only items with inline MIME attachments.
4: Migrate only items with Notes RTF bodies with bitmaps.
7: Migrate only items with one or more of the features listed above.
For example: MsgRequireAnyFeature=2 tells the Wizard to migrate only messages with inline MIME attachments.