Hi everyone,
Sorry if this is a very basic or silly question — I’m just a beginner with KNIME, and things have gone completely wrong since I upgraded to version 5.5.0 for windows yesterday.
Everything was working fine before the upgrade. Here’s exactly what happened:
The issue started when I opened a second KNIME session. It asked me to select a different workspace, so I did — a different folder with another project inside it.
It then asked me to import a .knwf file. Since I only had a regular project folder, I zipped it and renamed it to .knwf. The import failed with an error (I don’t remember the exact message), and KNIME did not restart properly.
I had to force-close both KNIME sessions using Task Manager.
After that, when I tried to go back to the original workspace where I had been working all day and made very important changes, nothing loaded. It gave me the normal start screen but showed no recent workflows, even though the project folder is still there and includes the workflow.knime file.
I tried to switch to that workspace again using File → Switch Workspace → Other and selected the correct folder where my workflow is saved. It does open, but KNIME shows me the same welcome screen with no project loaded, just the basic “New Workflow” and “Import Workflow” options — as if the workspace is empty.
I can clearly see the folder still exists and contains everything, including the workflow.knime file. But KNIME is not recognizing or opening it.
I’m really worried I may have lost all the work I did today, and it was very important. I’d really appreciate any help or suggestions on how to recover my workflow and get things working again. Please keep any advice beginner-friendly.
There may be more elegant ways to fix your problem, but when I have similar problems I use the brute force method of doing a new installation. Create a blank folder and download the zip version of KAP there. Unzip the download. Click on the “knime.exe” to start Knime. When it starts point to your existing workspace. In Windows you can create a desktop shortcut if you want. I don’t know other operating systems.
Thank you very much. I have downloaded it and I’m using the zip file to use it again. I also copied all my work to the KNIME default workspace. I think this is something I don’t know how to open properly, as this can’t be an issue for all users with this new release. I prefer to install it first and then work on it. Is there anyone who can help me with this issue and teach me how to use it? I was kind of panicking when I saw that I couldn’t open my project.
@Mobihashim01
Hello,
I am not an advanced user either but I wonder if you have followed any of the tutorials that are available ? If you have time I would suggest doing some of the them as I am sure that they will save you a lot of time and frustration.
You mentioned that when you opened the second Knime and it asked that you import a .knwf, but i dont understand why you would zip up a folder as workflow or I am just mistranslating your words. If you are in a Knime instance and you have workflow in a different “Workspace” then you can use File - Import workflow to bring a copy of the other workflow to your current Knime workspace.
Hi @mgirdwood , that would probably be on account of my suggestion here as a workaround to try to help resolve the problem initially. Yeah it’s not a mainstream suggestion but a knwf file is simply a zipped workflow renamed with “.knwf” instead of “.zip”
Hi @Mobihashim01 , I’ve been rereading your posts and it now has me wondering if you are mistaking the terms “workspace” and “workflow”.
Just to confirm, the “workspace” is the folder area on your drive into which all of the workflows you are working on reside".
Could it be that when KNIME asked you to tell it your current WORKSPACE, you actually pointed it at your current WORKFLOW?
That might not be what is happening, but the more I read of this and your previous thread, the more it makes me think that perhaps this is what has happened.
Please accept my sincere apologies for the confusion in my earlier message. I was panicking and didn’t explain things clearly. Let me clarify what happened:
I upgraded to the latest KNIME version and couldn’t find my projects anymore. I have two projects - one represents 4-5 months of work that I really didn’t want to lose. Before the upgrade, I was opening projects by selecting their folders directly, which worked fine.
After upgrading, my projects disappeared from the workspace. I tried switching workspaces and importing workflows, but nothing worked. I was getting confused between workflows and projects, which made my messages unclear.
The good news is I found the solution with the help of @rfeigel. His solution worked. I uninstalled KNIME, downloaded the zip file, and ran knime.exe directly. I moved my projects to the default knime-workspace folder, and now i can see my projects and i can load them into knime. I’m relieved a bit now.
Now I need help with the following things:
How do I update legacy nodes like “Column Expression (legacy)” to newer versions? Any quick tips or cheat sheets would be helpful. I will go through its documentation but any cheat sheet will be of great help.
I upgraded my laptop from i7/16GB RAM to i7 Ultra/32GB RAM, but it still slows down when running KNIME, PyCharm, and QGIS together. Any recommendations for better performance?
Since I started this as casual exploration, but seeing its power, I now want to switch to KNIME for data modeling and data preparation. I would like to learn it in depth to take on complex projects. Can anyone suggest a learning path, or if there are any certifications available I can pursue? Any formal materials or book recommendations would also be helpful. I would be sincerely grateful.
There’s no upgrade to the Column Expression (legacy) node. The KNIME developers are pushing the Expressions nodes, but have “promised” to keep the Column Expression node since many of us have used it extensively.
As to your performance issues, it would be best not to have a lot of other apps open when running Knime. You can change the memory allocated to Knime in the knime.ini file. @mlauber71 explains this in his Medium post, but here’s a little more detail. The default is 2048k. If you have 32g of installed memory you should be able to safely use 16g for Knime, although you may need to experiment a bit. Find the knime.ini file in your Knime folder and open it with a text editor such as Notepad or Notepad++. Find the -Xmx line and edit and save.
Finally, you don’t need to put your workflows in the default workspace. Any folder is fine as long as you point KAP to it. I keep my workflows on an external drive as follows:
but a knwf file is simply a zipped workflow renamed with “.knwf” instead of “.zip”
