Error selecting DataSet for AXDataSource in Visual Studio for Enterprise Portal development (AX 2012)

'm working on EP development for AX 2012 R2. When I try to add a DataSet that contains custom fields on standard tables or custom tables for a AXDataSource (in my EP user control) I receive this errors:

'DataSource "CustTable" in DataSet "DataSet1" has an unknown field "Field1"'

'Table with an id of "Table1" does not exist'

I tried to delete all the .auc files but I receive still the same problem.

At the moment I'm working with visual studio and the AOS installed on different machines.

Thanks,

Luca Ganz