Problem when generating a dataset


I have a problem when generating a dataset from my labelled images. I follow the steps, although after the proccess finishes, the page says: 1277 images (what it should have), Nevertheless, when I click on “view all images”, it says " This version is empty.

Upload or select images and annotations from your library to continue.". And when I download the dataset, only two .txt are in the .zip file, no image at all (not even the folder stucture of YOLO).

I found similar problems:
Generating new dataset version leave images empty - Community Help - Roboflow

Can not export dataset - Community Help - Roboflow

But I couldn’t fix it following those answers. Is there any problem currently? Could anyone help me with it?

Thank you in advance.

Best regards,


Here is the dataset, just in case you need it to check what’s wrong: deteccion - v16 2023-04-17 3:25pm (

Hey, Alberto.
I have had same issue and in my case it was caused by "" character in class name. I have had to change the class name manually and after that it is working correctly.

Thank you Juraj!

Actually, I change the name of a class in the step 3 (preprocessing), because it has a “/” character, but it still happens… So I don’t know what’s wrong…

I had to change every class containing “/” this character in dataset, remapping didnt help me.

Thank you. The only option I see is the preprocessing step. Is there any other way to change the name of the classes?

Thank you in advance

I dont know about any other option than do it manually.

Thank you Juraj, I am trying it. I could do the ones which could be changed manually (wrong label), but there are unused labels (indeed, the one with the character // is an unused label) and I cannot remove it… Do you have any idea on how to do it?

@Alberto, if there is an unused label, try clicking “Regenerate” on Health Check to see if it appears, still.

After all of the “problem” labels are removed, then delete the affected versions, and regenerate your dataset.

Thank you so much! I tried to regenerate. Indeed, some unused classes have disappeared. Nevertheless, the one which apparently creates the problem (//) still appears. It says it has 22 annotations. But when I click on it and search for the images which have that class, there is no result at all (when I click on another class, it returns to me the images).

So, in summary, there are 22 annotations with // but no image appears, therefore I cannot change/remove the label… Could you please guide me to solve it?

Thank you so much again!

I would recommend reaching out to Roboflow’s customer support team for assistance. They will be able to provide you with more personalized and specific help for the issue you’re experiencing. You can contact them through their support page or by emailing

In the meantime, you might also try generating the dataset again using a different method or platform to see if the issue persists. There are many other data labeling and dataset generation tools available online that you can try out.

If @Alberto can file a bug report here, actually, that will help us get it resolved: GitHub - roboflow/external-bugtracker

We have a guide for bug reports here as well: How to File a Bug Report - Roboflow

And for others that see this, our main support email is