tables and viewing issue is graphical designer

Hi,

I'm using Pentaho Community 3.6.1 to generate reports and BI Server Community 4.8.0. The data I'm working on are stored in a sql server 2005 instance and I use JTDS JDBC driver to connect to SQL Server instance. for around a week I was working with query builder graphical interface but now I can't view the tables and views I was working with while using JTDS but when I changed the connection method to ODBC everything works fine.
I have checked SQLServer permissions and they are in the correct level. I should mention that the query builder for another database on the same instance works fine.

Its an emergency condition, help as soon as possible.

thanks,