To test the Try it out button for your API: Discovering APIs in the API Catalog

Troubleshoot for “Try It Out” functionality

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Areas to troubleshoot when an error occurs
Error messages in the console
Resolution
CORS
`Access to fetch is blocked by CORS policy: Request header field authorization is not allowed by Access-Control-Allow-Headers in preflight response.`
Check if the CORS Restriction policy is enabled. The default CORS Restriction policy can be enabled in the Settings Panelfrom the Portal Manager, Enable Try Me checkbox.
Check Access Control Request Headers because it is a mandatory field if it not configured it can give an error.
Info
The CORS policy with a default setting provides a standard configuration.
Network Failure
`Network Error`
Check the Network Connectivity.
URL scheme in CORS settings dialogue box
`Mixed Content: The page<>was loaded over HTTPS, but requested an insecure resource<>. This request has been blocked; the content must be served over HTTPS.`
Use only “http” or “https” for the CORS request.
Check if the page is loaded over HTTPS matches the URL HTTPS scheme in the CORS request. If your page was loaded over HTTPS, and requested an insecure resource with HTTP, then an error occurs
FeedMaster and Load Balancer
`Failed to load resource: net::ERR_NAME_NOT_RESOLVED`
Check if there is at least one active FeedMaster node, a JCC node, and active Load Balancer.
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To delete an API, you must delete all versions and the assets in those versions. For details, see the following topics:
Deleting an API Version
Deleting Version Assets