---
title: Troubleshooting API client HTTP 4xx errors
description: The Apigee API gateway might return a 4xx error to the API client if the API client's request can't be authenticated by the PingAuthorize sideband API endpoint.
component: pingauthorize
version: 10.1
page_id: pingauthorize:pingauthorize_integrations:paz_apigee_integration_4xx_errors
canonical_url: https://docs.pingidentity.com/pingauthorize/10.1/pingauthorize_integrations/paz_apigee_integration_4xx_errors.html
revdate: August 14, 2023
---

# Troubleshooting API client HTTP 4xx errors

The Apigee API gateway might return a 4xx error to the API client if the API client's request can't be authenticated by the PingAuthorize sideband API endpoint.

To troubleshoot 4xx errors caused by authentication issues against the PingAuthorize sideband API, see [Policy decision data](../pingauthorize_server_administration_guide/paz_capture_debug_data.html).