---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/13299#article
headline: "13299: 2010 Conference API feature requested using 2008 API"
url: https://www.twilio.com/docs/api/errors/13299
inLanguage: en
dateModified: 2026-06-08T11:38:30.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 13299: 2010 Conference API feature requested using 2008 API

Log Type: APPLICATION

Log Level: ERROR

## Description

This error occurs when you request a conference feature that requires the `2010-04-01` Voice API, but the call or API request is still using the older `2008-08-01` API version. Update your conference workflow to use the current Voice API and make sure any call entry point is not starting the session with the older API version.

### Possible causes

* Your application is making a conference-related request through the deprecated `2008-08-01` Voice API instead of the `2010-04-01` Voice API.
* A Twilio phone number handling the call is configured with `apiVersion` set to `2008-08-01`.
* A TwiML Application handling the call is configured with `apiVersion` set to `2008-08-01`.
* Your call flow tries to use a conference capability that is available in the 2010 Conference API while the session is still running on the older API version.

### Possible solutions

* Update your Voice API requests to use the `2010-04-01` base path for conference-related operations.
* Update the phone number `apiVersion` for incoming voice calls to `2010-04-01`.
* Update the TwiML Application `apiVersion` to `2010-04-01` if your call flow starts through an Application resource.
* Review your conference workflow and remove or replace any conference feature that depends on the 2010 Conference API until the full call path has been upgraded.

#### Additional resources

* [Programmable Voice API Overview](/docs/voice/api)
* [REST API: Applications](/docs/usage/api/applications)
* [IncomingPhoneNumber resource](/docs/phone-numbers/api/incomingphonenumber-resource)