I have to make a SOAP callout to an Endpoint, Firstly I tested it with Postman and I was able to receive a successful response, But when I implemented it in Apex and executed the code I am getting an ERROR:
System.CalloutException: Unable to tunnel through proxy. Proxy returns "HTTP/1.1 503 Service Unavailable"
When I googled I found this might be an issue because of salesforce IP not whiteListed in my Endpoint server but when I confirmed them they said it's whitelisted already.
The endpoint is also added to the Remote site setting in salesforce.
can anyone please help me with this I wanted to fix these issues as soon as possible?
3 answers
Hi Vikas,
This problem is not on the Salesforce side - it's the proxy itself returning a 503 error. You need to analyse the logs from the proxy's side.
