Failed to start GDB server Error in initialising ST-Link device

[ADabl.1]

Hello folks,

I am new to STM32 and have been using it (STM32H7A3ZIQ) for a while, everything was fine with download and debugging codes until a week ago when STM32CubeIDE suddenly has stopped launching the debug session. An error msg -failed to start GDB server (see attached) pops out whenever I want to debug codes, I have been trying to resolve this very problem for the past week by following other people's solutions on Youtube, but all my attempts were in vain.

In addition, I installed different ST-Link programs provided by ST such that ST-Link server (Utility), STSW 004, 007, and 009. But even by doing so, I couldn't resolve this matter and no device found remains.

NB:

• Even after having updated my device (V3.J8.M3) by using ST-Link 007, STM32CubeIDE doesn't recognise it at all (no device found on target).
• ST-Link utility also cannot connect to the target

I hope someone could help me to get back coding.

I look forward to hearing your expert thoughts on how to resolve it.

BR,

AD

[khauenst321]

I began having the "failed to start GDB server" error after changing the version of STM32CudeIDE. The solution was to create a new Debug launch configuration using these steps.

Run > Debug Configurations... > New Launch Configuration*

* New Launch Configuration is the icon on the left of the Debug Configurations dialog window.

It may be necessary to copy some of the settings from a previously working launch configuration into the new one.

[Navaneethan]

Hello ADabl.1,

I understand your frustration with the STM32CubeIDE not launching the debug session and the issues with the ST-Link connection. I experienced a similar problem recently with my STM32F401CCU6, and I found a solution that worked for me.

Solution:

The key was to press both the RESET and BOOT0 buttons on the MCU during the programming and debugging process. Here's the step-by-step procedure that resolved my issue:

1. Connect Your STM32 to Your Computer: Ensure your STM32 board is connected to your computer via USB.
2. Set BOOT0 to High: Press and hold the BOOT0 button. This puts the microcontroller into system memory boot mode, allowing it to enter the built-in bootloader.
3. Press RESET: While holding the BOOT0 button, press the RESET button on the MCU. This action resets the microcontroller and ensures it starts in bootloader mode.
4. Release RESET: Release the RESET button while still holding BOOT0.
5. Release BOOT0: After a few seconds, release the BOOT0 button. This sequence ensures that the microcontroller enters a state where it can be reprogrammed and debugged.
6. Start Debugging in STM32CubeIDE: Open STM32CubeIDE and attempt to start the debug session again.

Additional Tips:

• Update Firmware: Ensure your ST-Link firmware is up to date. You've already updated to V3.J8.M3, which is good.
• Check Connections: Double-check all connections between your ST-Link programmer and the MCU. Loose connections can often cause issues.
• Try Different USB Ports/Cables: Sometimes, the issue might be with the USB port or cable, so try different ones if possible.
• Reinstall STM32CubeIDE and ST-Link Utilities: As a last resort, uninstall and reinstall the STM32CubeIDE and ST-Link utilities.

After following these steps, my STM32CubeIDE successfully recognized the device, and I was able to debug my codes without any issues.

I hope this solution works for you as well. Please let me know if you need any further assistance.

Best regards, 
Navaneethan.

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[Ebrahim]

Dear Navaneethan, 

Thank you for providing the detailed steps, I had a similar issue with STM32F429I Discovery Board and it worked for me. 

Best regards,

Ebrahim 

[brkkc06]

Hello everyone,

I was getting Failed to start GDB server Failed to start GDB server Error in initializing ST-LINK device. Reason: (2) ST-LINK DLL error.; errors.I solved these. Hopefully, it works for everyone.

First, I will mention the hardware. I am using the Nucleo-F411RE board. I bought it in August 2025. I am not sure if it is original or not. To solve these errors, I watched many videos and read numerous comments and articles. In the end, I managed to solve it with my own attempt.

Required programs:

• ST-LINK Utility

• STM32CubeIDE

Finish downloading and complete the installations.

STEP 1 :

Run ST-Link utility. Then connect stm32 board to your computer's.

STEP 2 :

Click on the ST-LINK tab in the ST-LINK Utility. Then, click on the Firmware update option.

STEP 3 :

Click on the Device Connect then click on the "Yes >>>" button.

After the installation is complete, remove your STM32 board and reconnect it to your computer. You are done with the ST-LINK Utility, so you can close it. Then, open the STM32CubeIDE program. When you try to run a debug session, it will notify you that an update is available. Perform the update. After that, remove and reconnect the board again. To confirm that your issue is resolved, try debugging once more.

This worked for me.