Error
Expected XML node type was XmlDeclaration, but actual type is Element.
Cause
This normally indicates that the server is unavailable or under stress and, as a result, is returning unexpected XML content when accessed using the EWS (Exchange Web Services) API.
Resolution
Solve this issue by performing the following steps:
- Check if the Exchange server is responding and can be logged into using OWA.
- Resubmit the migration if it failed, or submit your mailbox in Retry Mailbox Migration Errors mode after the mailbox has successfully migrated.