Database Connector (MS SQL): Java Runtime environment not supported

Dear all,

I am new to KNIME and would like to setup a workflow using an MS SQL database connection.

I read all the instructions and forum posts I could find related to this.

My connection string looks like this: "jdbc:sqlserver://" (subdomain and company name substituted).

I verified both port (1433) and database name as well as user name and password, but I'm still getting following error message: 

"java.sql.SQLException: java.sql.SQLException: java.lang.UnsupportedOperationException: Java Runtime Environment (JRE) version 1.7 is not supported by this driver. Use the sqljdbc4.jar class library, which provides support for JDBC 4.0"

sqljdbc4.jar (as well as sqljdbc.jar) is listed in the "Database Driver" tab of the KNIME configuration and is at the top of the list. I also tried to manually add a separate sqljdbc4.jar that I downloaded from Microsoft, but the problem persists.

I'm not sure why it does not find sqljdbc4.jar, as it is clearly present and seems to be configured properly. I also tried adding sqljdbc4.jar and sqljdbc.jar to the CLASSPATH variable, but it didn't help.

I appreciate your help.


You can only use one of sqljdbc4.jar or sqljdbc.jar. Remove the latter from the list of registered drivers in the preferences, restart and then it should work.

It was really as easy as that. My installation had all of the drivers preconfigured, so I thought it is supposed to be like that. Thanks for your fast help!