---
title: "How to Check Phone for a Valid Device Certificate"
slug: "how-to-check-phone-for-a-valid-device-certificate"
updated: 2026-05-22T19:36:54Z
published: 2026-05-22T19:36:54Z
canonical: "help.8x8.com/how-to-check-phone-for-a-valid-device-certificate"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.8x8.com/llms.txt
> Use this file to discover all available pages before exploring further.

# How to Check Phone for a Valid Device Certificate

## Objective

Checking your third-party (non-8x8 purchased) phone for a valid Device Certificate.

## Applies To

- Third-Party Devices
- Device Certificate

## Procedure

> [!NOTE]
> *Note:*
> 
> *Accommodation of devices not purchased from and originally provisioned for service by 8x8 is best-effort. These devices are not guaranteed to be supported on 8x8 service.*

Before attempting to provision a third-party phone for 8x8 service, you should check your device for a valid, **factory-issued device certificate**. You will then be able to provision your device for 8x8 service. The certificate *must* be factory-installed, and not added by another party later. *(*[What are device certificates and why are they important?](/support/docs/what-are-device-certificates-and-why-are-they-important)*)*

8x8 allows provisioning of third-party phones from the manufacturers below.

### Cisco

For full instructions on configuring Cisco phones see [Provision Your Cisco SPA IP Phone](/docs/viewArticle.html).

Follow these steps to determine whether a valid, factory-installed Device Certificate is on your phone

1. Connect the phone to the network and power it on. (If you will be using a computer to complete provisioning setup, ensure the phone and computer are on the same VLAN/subnet.)
2. Via the phone menu, verify that the device has a valid installed client certificate.
  - SPA303 and SPA504G: Press **Menu** > **10: Product Info** > **6 (Certificate: Installed)**
  - SPA525G2: Press **Menu** > **10: Status** > **1: Product Info (Certificate: Installed)** *You should see the message* ***Certificate: Installed****. If you do not see this, the phone cannot be provisioned for use with 8x8. Please contact the phone's previous owner or the previous service provider for assistance.*

### Poly

For full instructions on configuring Poly phones visit ![](https://cdn.us.document360.io/e3a59e39-abd3-4423-964c-0a4008dc5673/Images/Documentation/global_doc.gif?sv=2026-02-06&spr=https&st=2026-11-03T23%3A04%3A20Z&se=2026-11-04T00%3A04%3A20Z&sr=c&sp=r&sig=Tu9uh1F3EVGPDVC2wx%2BSxPaVfPfUbHDInchcnDcmxLk%3D) [Reusing Poly Phones with 8x8 Service](https://cdn.us.document360.io/e3a59e39-abd3-4423-964c-0a4008dc5673/Images/Documentation/Polycom-Reuse-Setup-v2-5-pm375211.pdf?sv=2026-02-06&spr=https&st=2026-11-03T23%3A04%3A20Z&se=2026-11-04T00%3A04%3A20Z&sr=c&sp=r&sig=Tu9uh1F3EVGPDVC2wx%2BSxPaVfPfUbHDInchcnDcmxLk%3D).

1. Press the **Menu** key and scroll past **Features** to **Status**.
2. Select **Status.**
3. Select **Platform.**
4. Select **Phone.**
5. Read the message:
  - If the message says **Device Certificate: Factory Installed**, your phone is supported on 8x8 service.
  - If the message says **Device Certificate: Not Installed, Device Certificate: Invalid** or if there is no device certificate message at all, **the device is not supported on 8x8 service**.

### Yealink

For full instructions on configuring Yealink phones visit ![](https://cdn.us.document360.io/e3a59e39-abd3-4423-964c-0a4008dc5673/Images/Documentation/global_doc.gif?sv=2026-02-06&spr=https&st=2026-11-03T23%3A04%3A20Z&se=2026-11-04T00%3A04%3A20Z&sr=c&sp=r&sig=Tu9uh1F3EVGPDVC2wx%2BSxPaVfPfUbHDInchcnDcmxLk%3D) [Reusing Yealink Phones with 8x8 Service](https://cdn.us.document360.io/e3a59e39-abd3-4423-964c-0a4008dc5673/Images/Documentation/Yealink-Reuse-Setup-pm5700815-2017.pdf?sv=2026-02-06&spr=https&st=2026-11-03T23%3A04%3A20Z&se=2026-11-04T00%3A04%3A20Z&sr=c&sp=r&sig=Tu9uh1F3EVGPDVC2wx%2BSxPaVfPfUbHDInchcnDcmxLk%3D).

1. Press the **OK** key.
2. Press down to select **More...**
3. Select **Phone.**
4. Scroll down to **Device Cert**, then read the message:
  - If the message says **Device Certificate: Factory Installed**, your phone is supported on 8x8 service.
  - If the message says **Device Certificate: Not Installed, Device Certificate: Invalid** or if there is no device certificate message at all, then the phone is not supported on 8x8 service.