I'm having trouble with the Upload node, when connecting to S3 and trying to upload a .csv file I get this error:
Execute failed: Unable to execute HTTP request: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
The Amazon S3 connection node is set properly and testing the connection everything looks fine.
I'm using the last version of KNIME (3.4.1) but I tried to download an old one (KNIME 3.3.1) and it still didn't work.
Also, I imported the workflow from another laptop where it worked properly (KNIME 3.3.1), and I didn't change any setting in the Upload node or in the Amazon S3 connection node. The workflow still works on that laptop and on other laptops connected to the same network, so it must be definitely something machine-related.
Thanks for your help.