Old H2O model produces Incompatible port spec with H2O predictor

Dear H2O and KNIME users,

almost two years ago we produced a model with H2O using the workflow from knime://EXAMPLES/04_Analytics/11_Optimization/08_Model_Optimization_and_Selection. As the model was pretty good we used it further and I saved it with KNIMEs model writer (I think (hope) at that time the MOJO nodes were not available) now the problem I have is that the H2O Predictor (Classification) gives an error with: "Incompatible port spec at port 0, expected: H2OModelPortObjectSpec, actual: H2OFramePortObjectSpec".
It worked before, but now I cannot execute the workflow due to this error.

I saved the model again from the saved workflow (with the KNIME-model-writer) now I can execute the same workflow, however my predictions for ~270 molecules have changed and that is what worries me the most. Writing the model with the mojo writer also changes the predictions.

I would be happy to provide a workflow (along with the data) however I could only do so privately (via email or private message) as the models and data should not (yet) be made public.

Thanks for your help!

Hi @jenniferh,

I am happy to investigate this! There might have been a bug that caused actually wrong results, so I would assume that the results you get now are more correct. However, you are welcome to send me your files in a private message, so that I can take a look at it.


Hi @SimonS,

thanks for the quick reply. While building a smaller workflow for you the problem with the different predictions resolved itself (It is the exactly same workflow just a bit cleaned up, however in between I got the error Execute failed: Frame frame-0c0752dc-cea5-4611-aff6-28d64153cb8f doesn't exist on cloud anymore. Please re-execute workflow! which prompted me to try it again with a new local context node, now it works out. Sorry for that.

The error with the cell however persists, is there anything we can do to make sure that models will be useable in future versions without needing the original workflow for that?

Thanks and sorry again,

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Great to here, @jenniferh!

You mean this error: "Incompatible port spec at port 0, expected: H2OModelPortObjectSpec, actual: H2OFramePortObjectSpec".?
I have never seen this error. Usually, it should work to load older models with a newer KNIME version. Would it be possible for you to share this model with me, so that I could take a look what is going wrong?


Thanks, that would be helpful!
Yes of course, do you have an email or is it possible to share something in a private message here (sorry for that but I did not find the possibility :sweat_smile: )?


I have sent you a message, @jenniferh.