Import a organization to a new domain.

I'm trying to import an organiaztion from a database i got from client. It's in a different domain than the database. 

I keep getting the error: 

You must map your Active Directory user account to at least one enabled Microsoft Dynamics CRM user who has the System Administrator security role before teh organization can be imported. 

Already tried: 

1. Exporting the mappings file, and specifying new domain, still not working

<MappingConfiguration>
<UserMapping old="Domain1\User1" new="Domain2\CRMServiceAcct" />
<UserMapping old="Domain1\User2" new="" />
<UserMapping old="Domain1\User3" new="" />
<DomainMapping old="Domain1" new="Domain2" />
</MappingConfiguration>