When processing a dimension caught the error "Errors in the OLAP storage engine: A duplicate attribute key has been found when processing: Table: 'dimension', Column: 'attribute', Value: 'reclamação'. The attribute is 'attribute'.".
Analysing the data source found two records:
1 Reclamação
2 Reclamacão
The requirement was that these two values are the same. So, the error was because SSAS issued a distinct count for the attribute using the column collation and then used the SSAS collation. The collation of the database was "SQL_Latin1_General_CP1_CI_AI" and the collation for SSAS was "Latin1_General_CI_AI".
The solution was changing the collation of the database column from "SQL_Latin1_General_CP1_CI_AI" to "Latin1_General_CI_AI".
This link help a lot.
Regards,