Labelbox documentation

Validate dataset

When you upload your dataset into the Labelbox app, Labelbox automatically runs validation checks to determine whether the CORS setup was configured properly, whether Labelbox can successfully fetch data from your S3 bucket, and if Labelbox can properly sign the URLs.

To check the integration status for your dataset, select your project, go to Settings > Datasets, and click on the dataset. From there you can click the refresh icon to view the error messages.


Error message


"Incorrect CORS header..."

Ensure your S3 bucket is configured to serve appropriate CORS headers ( and See our docs for setting up CORS headers.

"Cannot access data row..."

Make sure the IAM integration for the dataset is valid and that the S3 URLs are correct.

Make sure the role you created for Labelbox in your AWS account has GetObject access to your S3 bucket.

Click on the dataset's name to navigate to the dataset details page. Click on a link on one of the data rows and use the response from the server to understand why the request is failing.

To learn how to validate your dataset programmatically, see our GraphQL docs.