HttpClient is not working on some machine in the same network

Symptom

When accessing the Web Service API using an HttpClient object, some machines fail to send requests in the same network segment.

Environment

PowerBuilder 2019 R3 & later

Cause

When the HttpClient object sends a request, it uses the Internet Explorer’s LAN Settings by default. The issue happens when different client machines have different proxy settings or the "Automatically detect settings" checkbox of LAN Settings is checked on the client machine.


Solution

Check the client machine’s LAN Settings, make sure the proxy settings are the same and make sure the "Automatically detect settings" checkbox is unchecked.