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Dynamics 365 Community / Forums / Customer experience | Sales, Customer Insights,... / D365 Salesforce REST A...
Customer experience | Sales, Customer Insights,...
Suggested Answer

D365 Salesforce REST API error: Unable to tunnel through proxy. Proxy returns "HTTP/1.1 503 Service Unavailable

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Posted on by Aratrika 5

Hi,

I am very new to D365 world. I am trying to connect Salesforce to D365 to fetch Opportunity records from D354 to Salesforce. 

I have all setup completed (client ID, secret and REST API class in SF) but when I send REST Request to D365 from Salesforce, I am getting this response 

Unable to tunnel through proxy. Proxy returns "HTTP/1.1 503 Service Unavailable

Something related to whitelist IP address but not sure where to add Salesforce IP address to whitelist in D365.

Thanks in advance. 

I have the same question (0)
  • Suggested answer
    Nya Profile Picture
    Nya 29,064 on at

    Hi,

    Please refer to the following blog.

    Why System.CalloutException: Unable to tunnel through proxy. Proxy returns “HTTP/1.1 503 Service Unavailable” occur (gavan.in)

  • Aratrika Profile Picture
    Aratrika 5 on at

    Hi Nya,

    Thanks for the reply. I have this D365 trial org just practice Salesforce & D365 integration. There shouldn't be any firewall issue since it's in my private network (no VPN involved). Moreover, Salesforce IPs need to whitelist in the D365 network not other way around.

    The other 2 reasons might not be related since I am not using any certificates (just client Id and secret from REST API).

    Hope that make sense to you

  • Suggested answer
    Bipin D365 Profile Picture
    Bipin D365 28,985 Moderator on at

    Hi,

    Would you be able to share your code to troubleshoot this issue?

    I hope you have created the Application User in D365 using Client Id and assigned security role.

    Please mark my answer verified if this is helpful!

    Regards,

    Bipin Kumar

    Follow my Blog: xrmdynamicscrm.wordpress.com/

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