Problem connection to local SQL Server 2017 installation

Hello everybody

I am having a problem connecting to a local MSSQL Server instance:

Microsoft SQL Server Developer (64-bit) 14.0.1000.169
KNIME 3.5.2 using the integrated Microsoft SQL Server Connector.

I am using these connection settings:

Error: ERROR Microsoft SQL Server Connector 0:1 Execute failed: Could not create connection to database: Connection refused: connect

The users are created on the sql server and working (tested with Management Studio).

The SQL Server is on the same Windows 10 machine as KNIME but I am not able to log in. The weird thing is that I don’t even see the login-attempt in the SQL Server Logs (with logging for every login attempt turned on) therefore I wonder if something strange is going on. It seems to be such a basic thing to connect these two systems that it practically can’t go wrong like that :persevere:

What am I doing wrong? Is the Connector Plugin outtdated? Is my Version of SQL Server not supported (yet)? Is the Developer Version somehow not supported? Does anybody have an idea?

Thanks =)

This looks like you are either connecting to the wrong port or the database isn’t listening on TCP ports at all. The driver can’t get a connection to the database therefore you also don’t see anything in the database logs.

Yes, well I didn’t even imagine the possibility that the server is not open for TCP/IP connections by default.

netsat -an shows nobody is listening on 1433, so…


Enable TCP/IP Connections in SQL Server Configuration


Hopefully someone saves some hours reading this :smirk:


This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.