KNIME SDK 3.1.0 on OSX / Java 1.8 can't launch application

I just moved from 2.12 to 3.1.0 but I'm now having trouble launching (hitting the play or debug button) Knime from within the SDK.  I got this error:

Potential deadlock in SWT Display thread detected

I also tried 3.0.0 with same error.  Has anyone with any luck developing in 3.x on OSX?

This is only a warning message, note the "potential" in the message. This detection is not 100% accurate. If you don't experience any problems in the GUI then you simply ignore it.

The test session nor the debug session didn't even start though.  It got stuck at the splash screen and this deadlock message at the SDK console.  And at the splash, it stuck on this message "Loading org.eclipse.e4.ui.css.swt".  Thanks Thor.


it's just wild guessing, but could you try changing the "Use the -XStartOnFirstThread argument when launching with SWT" checkbox in Run Configurations -> Arguments Tab? Is it checked for the configuration that fails to start?



Hi all,

We have had experienced the same problem and we can work around it by deleting the .metadata folder. The downside of this approach is that all loaded workflows will be lost.


AlexanderFillbrunn, the "Use the -XStartOnFirstThread" checkbox was checked and the argument does contain -XStartOnFirstThread.  Removing it would cause a failure.  I tried chahuistle's suggestion to blow away the .metadata directory.  That solved my problem.  Thanks!

I had the similar problem with KNIME 3.1 not starting from eclipse on OSX and found a way to reproduce it:

1. Start KNIME 3.1 from eclipse with a new workspace
2. Drag any KNIME node to the "Personal favorite nodes" folder.
3. Close KNIME and start it again:
 KNIME will load forever with the message ``loading org.eclipse.e4.ui.css.swt``

I stepped through the code and the error happens when the following method is called: UIManager.setLookAndFeel(String laf);

One example is line 249 in the  class: "org.knime.core.node.Node"

I hope this helps with finding a solution to this bug.

I upgraded to KNIME 3.1.1 from KNIME 3.0.1 and had the same problem.

The problem that I had was that the location of the workspace data for my runtime was the same for both KNIME versions. So I simply used a new folder. The default location is:


Changing the location of this folder solved the issue for me (which is, of course, similar to deleting the .metadata folder of the running configuration folder, but I was deleting the .metadata folder of the SDK!).