"Your request is prohibited because the request is on loopback from external IP."

[MarkelioH]

Environment Details

If you are using Assisted Modeling tools in Designer and the machine is behind a Proxy Server, you might get the error mentioned in the article.
 

• Alteryx Designer + Intelligence Suite
  • 2020.x Versions
• Third-Party Products: Proxy Server (Manual Proxy or PAC script)

 

Error: "Your request is prohibited because the request is on loopback from external IP."

 

Error: "The request URL could not be retrieved" 

 

Cause

Calls to localhost are not allowed in the Proxy Server.
If the machine when running Designer is behind a manual Proxy server, you may need to allow bypass proxy server for local addresses or add an exception.
If the Proxy Server is configured to use a PAC script, you may need to allow direct access in the PAC script for calls to localhost.

Resolution

Solution A - When using a Manual Proxy server

 

1. Close Alteryx Designer
2. Open Internet Options > Connections > LAN Settings
3. Uncheck the "Automatically detect settings" option
4. Make sure the manual Proxy server is checked and the "Bypass proxy server for local addresses" is checked as well

 

   5. Restart Alteryx Designer and test the workflow. 
If you are still getting the same error, you might need to add an exception in the Advanced window of Internet Options > Connections > LAN Settings > Advanced


 

Solution B - When using a PAC script

When using a PAC script, you may need to work internally with your IT/Proxy Team to allow direct access in the PAC script for calls to localhost.

 

[Istwineres]

For general information: this solution resolved my problem for the Python tool on Alteryx Designer installed on Server ("Self-referential requests to proxy are forbidden")