Reason: CORS preflight channel did not succeed

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Reason

Reason: CORS preflight channel did not succeed

What went wrong?

The {{Glossary("CORS")}}  request requires preflight, preflighting could not be performed. There are a couple of reasons why preflighting might fail:

• A cross-site request has previously been performed that already did a preflight, and doing the preflight again is not permitted. Make sure your code only preflights once per connection.
• The preflight request suffered any kind of networking error that might ordinarily occur.

See also

• CORS errors
• Glossary: {{Glossary("CORS")}} 
• CORS introduction