with Pentaho MetadaEditor, i want to create a new connection to MS SQL Server, when i created this connection i have this probleme:

Unable to retrieve database information because of an error

Error occured while trying to connect to the database

Error connecting to database: (using class net.sourceforge.jtds.jdbc.Driver)
Server has no instance named INSTANCE1.

in information connexion :
nom connexion: MyconnectionSqlServer
Fournisseur base de données: MS SQL SERVER
Méthode d'accée: Native (JDBC)
nom du serveur hote: localhost
Nom de la base de données: MyDataBase
Numéro du port: 1433

this information is in "General".

In "Options":
type base de données : MS SQL SERVER
Paramétre : instance
Valeur ; INSTANCE1

Please any one can help me why this problem to connect SQL Server