---
title: Resolving URL-related errors
description: Review and update the URL of the identity provider (IdP) initiated single sign-on to resolve the 404 Not Found and System Error error messages.
component: pingfederate
version: 13.1
page_id: pingfederate:administrators_reference_guide:pf_resolving_url_rel_errors
canonical_url: https://docs.pingidentity.com/pingfederate/13.1/administrators_reference_guide/pf_resolving_url_rel_errors.html
llms_txt: https://docs.pingidentity.com/pingfederate/llms.txt
docs_for_agents: https://developer.pingidentity.com/build-with-ai/docs-for-agents.md
revdate: July 5, 2022
section_ids:
  example: Example
---

# Resolving URL-related errors

Review and update the URL of the identity provider (IdP) initiated single sign-on to resolve the `404 Not Found` and `System Error` error messages.

If a user encounters a `404 Not Found` status or a `System Error` message, check the URL of the request.

## Example

Examples

* 404 Not Found

  `https://sso.idp.local/idp/startSSO.ping&PartnerSpId=sp1&TargetResource=https%3A%2F%2Fapp.sp1.local%2F` causes a `404 Not Found` error, because the separator between the path of the URL and the first query parameter is incorrect. The correct separator is a question mark `?` and not an ampersand`&`.

* System Error

  `https://sso.idp.local/idp/startSSO.ping?PartnerSpId=sp1?TargetResource=https%3A%2F%2Fapp.sp1.local%2F` causes a `System Error` message, because the second query parameter separators are incorrect. The correct separator is an ampersand `&` and not a question mark `?`.

|   |                                                                                                                                                                                                                                                                                                                                              |
| - | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
|   | You must also use ampersands for all subsequent separators between additional query parameters in the URL.In addition, you must URL-encode query parameter values that contain restricted characters. For information about URL encoding, see, for example, [HTML URL-encoding Reference](https://www.w3schools.com/tags/ref_urlencode.asp). |

For both sample issues, update the URL of the IdP-initiated single sign-on (SSO) to the following URL:

`https://sso.idp.local/idp/startSSO.ping?PartnerSpId=sp1&TargetResource=https%3A%2F%2Fapp.sp1.local%2F`