How Do I Resolve a CORS Error?

To resolve CORS issues, the REST endpoint that you're connecting to must have CORS support for the Visual Builder domain. For example, if you're connecting to an Oracle REST Data Services (ORDS) endpoint, the ORDS endpoint's list of allowed origins must include the Visual Builder domain; in other words, the domain from where the ORDS REST API is being called (for example, https://sample.builder.oraclecloud.com).

If there's a typo or a mismatch in the CORS configuration at the endpoint, you're likely to run into this error:

The REST API that you are connecting to doesn't seem to have Cross Origin Request sharing (CORS) for the Visual Builder domain. 
Try again after adding necessary CORS settings for the REST API you are connecting to.

To fix this, you can either change the service connection's Connection Type to Always use proxy, irrespective of CORS support, or enable the endpoint to support CORS for the Visual Builder domain.