Now submissions are working (thanks admins!!) I see I’m not alone in getting inference failed error messages.
In my case it’s because I’ve got inconsistencies between the feature names of my locally trained model and the features names I’ve put in the prepare_data routine of the zip file submission.
Sharing in case it helps other’s get their submission fixed before the extended deadline.
Turned out I then hit another error which may worth @alfarzan investigating and other R zip file submission people that have recently upgraded to xgboost 1.3 and are getting submission errors also trying.
I upgraded my local version of xgboost to 1.3 which for R users was released on CRAN in the last week. Anyhow after the upgrade I’ve not been successful in making submissions from locally trained zip file, even though they pass all the local tests as per the zip instructions (and I’ve been making successful zip based submissions in previous weeks with xgboost 1.2.)
Anyhow after I downgraded my local version of xgboost back to 1.2, retrained, re-ran tests which again passed and then reloaded my submission then worked.
Could it be that AICrowd is loading xgboost 1.2 for R users and the models trained with the new 1.3 version have incompatibilities causing submission errors? In which case guess I need to specify my version of xgboost in install packages.
Thanks @nigel_carpenter
Yes this is true. We were not expecting packages to not be back-compatible in this way.
I will make an announcement about this issue tomorrow after the leadeboard.
From tomorrow we will be:
install.R script or the install_packages function on colab.Thanks for figuring it out!
I also had an Inference failed errors during the Generating Prediction Debug phase.
it says:
Error in x[[jj]] <- v :
attempt to select more than one element in integerOneIndex
In my enviornment everythings works and I have just added a line a piece of code with a case_when.
Do you have any idea why I am getting this error?
I really cannot solve it
Hi @pejo92
That looks to be an indexing error from R. Can you please link me to your submission ID and I can try to have a look 
Hi,
I also get the same error and couldn’t figure out where it is coming from ( Submission #114123). Any ideas what might be causing this?
Hi @sina1374
I’m sending you the traceback privately.
For clarity, the reason you are not getting the full traceback is that the evaluation works in 4 stages:
We give you tracebacks on steps 1 and 2. Full traceback on step 3 is not provided to reduce the risk of data leakage. Step 4 is from our side and should very rarely contain an error
Hi @alfarzan
I figured out that there was problem in my code.
I realized it is possible that we have new make_model, compared to what we have in our train dataset, isn’t it?
Yes! just like a real insurance company may encounter vehicles they’ve never seen before in a new year, so can your model.
But this fact doesn’t extend to other categorical features since they have much fewer unique values.
That’s right! Make super sense to me, thanks! 
Hi @alfarzan,
My latest submissions (e.g. 114780) have encountered a problem with the same error message, which this thread is reffering to: “Inference failed. View the submission for more details.”.
In the log I can find following detailed error message:
“Error in load_model(model_output_path) :
unused argument (model_output_path)”
I really can’t find any solution. Can you please take a look at my submission?
Hi @imfilip
This was a small issue from our side, can you please try again? and please copy a new neotebook (or reset your notebook to factory runtime).
Thanks for catching it! 
I’ve made a clarification post about this as well.