As a workaround please do not remigrate the whole migration plan again, but extract failed mailboxes in separate migration plan and execute it.
If you are trying to rerun a migration plan due to interruptions/errors in general, then perform a "Copy" on the plan, and include only those interrupted or failed mailboxes, so that the successful ones do not count against the mailbox migration limit.
Further information and configuration steps are in the "Copying Migration Plans" section of the ODME Users Guide on the following URL:
If your migrations are running, then the Copy feature is not available.
You can run the Copy feature on migrations that have the following statuses:
Further information and setup steps are also in this KB article:
The BugID for this issue is PT119268395 and was resolved with the latest ODME 18.104.22.1687 version that was rolled out on May 12th, 2016.
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