Yealink Phone Recovery Using TFTP

TELIN  |  Technical Support Knowledge Base

Use this guide to prepare a Windows PC as a TFTP server and recover a supported Yealink phone that cannot start normally. The procedure uses PumpKIN and the recovery package for the exact phone model.

When to use recovery

• The phone repeatedly restarts or becomes stuck in a boot loop.
• The phone remains on the Welcome or Initializing screen without completing startup.
• Startup problems continue after normal troubleshooting and a factory reset.

Recovery may resolve corrupted firmware or an interrupted upgrade. It does not repair faulty hardware. Confirm that the phone has a working power supply and network connection first.

Before you begin

• ​A Windows PC and a wired connection to the same subnet as the phone.
  
• PumpKIN TFTP Server and internet access to download the required files.
• The correct recovery package and model-specific recovery instructions.
• Stable phone power through PoE or a compatible power adapter.
  

Important: Recovery may reset settings. Back up the configuration if accessible and be prepared to reprovision the phone. Keep power connected throughout the firmware update.

Model differences: This guide covers phones with an on-screen TFTP recovery menu. Startup keys and menu options vary. DECT bases and other devices without this menu require their own recovery procedure. Some newer phones offer a built-in backup system instead. [1, 2]

1. Prepare the recovery files

1. Confirm the exact model from the device label. Obtain its recovery package from your phone provider or Yealink Support.

2. Extract all required files into a dedicated folder, for example C:\YealinkRecovery\T54W. This folder name is an example only.

3. Use the filenames specified in the package instructions. A normal firmware file alone may be insufficient; some models also require .bin or .rfs files. [2]

2. Install PumpKIN and configure file access

Download PumpKIN 2.7.3 for Windows

1. Expand Assets on the release page and download the Windows installer. Install and open PumpKIN.

2. Select Options, then open the Server tab. Apply the settings below.

Figure 1  PumpKIN Server options before configuration

The screenshot shows the initial settings. Replace C:\WINDOWS\system32 with your recovery folder and change the read and write selections as listed above. The phone downloads files from PumpKIN; no manual Send File action is needed.

3. Configure the network settings

1. Open Command Prompt and run ipconfig. Under the connected Ethernet adapter, note the IPv4 Address, Subnet Mask, and Default Gateway.

2. In PumpKIN Options, open the Network tab and apply these settings.

Figure 2  PumpKIN Network options before entering the PC address

3. Click OK to save. Keep PumpKIN open and its TFTP server enabled.

Allow PumpKIN through the active Windows or endpoint firewall for the phone’s local network. TFTP starts on UDP port 69 and uses additional UDP ports for the transfer. Use a scoped application rule rather than disabling the firewall. Run the server only on a trusted recovery network and close it afterward.

4. Start recovery on the phone

1. Follow the recovery package instructions to enter recovery mode. On many desk phones this involves holding a recovery key while reconnecting power, but the key can be Speakerphone or Redial depending on the device and firmware. Do not assume one key applies to every model. [1, 2]

2. Select TFTP if the recovery menu offers multiple methods. Follow the menu labels; option numbers can vary.

3. Enter the recovery network settings shown below. [1]

Example only: If the PC is 192.168.10.20 with mask 255.255.255.0 and gateway 192.168.10.1, use an available phone address such as 192.168.10.21. Set TFTP Server to 192.168.10.20. Substitute values appropriate to your network and verify that the phone address is unused.

4. Confirm the settings using the key or on-screen control indicated by the phone. Watch PumpKIN for file requests and transfer activity.

5. Allow the phone to download and install the files, then complete startup. A completed transfer in PumpKIN does not mean the phone has finished writing firmware. Keep power connected until recovery finishes. [2]

5. Verify and return the phone to service

• Confirm that the phone reaches its normal home screen and check its firmware version.
• Restore the intended network configuration and reprovision the phone through the normal PBX process.
• Confirm registration and test inbound and outbound calls with two-way audio.
• Close PumpKIN and remove any temporary firewall exceptions. Restore the PC network settings if they were changed.