Must toolchain version match SDK version?

RE: Must toolchain version match SDK version?

Erlend Isachsen — Tue, 10 Jun 2025 07:55:26 GMT

Thank you for the advice.

For anyone else struggling with the same issue, I want to add that you can alternatively use version 2024.12.55 of the nRF Connect extension. This version works for me, and I can flash etc. normally. To install a specific version in VSCode, navigate to extensions -> nRF Connect for VS code and click the arrow next to "uninstall", and select "install specific version...". Not sure how well it works with the very latest versions of SDK/toolchain, but I have used it the last 6 months or so without any problems.

RE: Must toolchain version match SDK version?

Edvin — Fri, 06 Jun 2025 19:12:55 GMT

I understand. We are struggling with reproducing this issue at the moment, but I have forwarded all your logs and generated support information to our VS Code extension team, so right now I don't know if I can do much more. I will get back to you in this ticket when I know more.

In the meantime, I suggest that you build and flash in a command window, outside the VS Code (but you can still use VS Code to navigate, and write code, and open your current build folder, for debugging purposes).

If so, I recommend that you set up a neat way to activate the toolchain and SDK location through a simple command.

One easy way to do this, up until v3.0.0 (not working on v3.0.0 or newer) is to use the nRF Connect for Desktop -> Toolchain manager, and Generate Environment script:

This will generate a .cmd file containing all paths that you need. Call it full_environment_2.4.0.cmd. Place it in a folder, and put that folder in your computer's path, so that it will be found from wherever you are running a command line.

Then, you can create a file, and call it "NCS_v2.4.0.bat", or something like that, and place it in the same folder. In that file, write the following:

@echo off

echo Setting up full Zephyr environment...

call full_environment_2.4.0.cmd

echo done!

Now, you should be able to open a command window in any folder by writing "cmd" where the path is usually written:

And hit enter. This will open a terminal in that folder. In there, type "NCS_v2.4.0", and it will print:

Setting up full Zephyr environment...
done!

And from there, you can use all west commands, like "west build -b nrf52840dk_nrf52840 -d build", "west flash -d build", and so on. Also note that when you make changes to an application with an exisiting build folder, you don't need to specify the board name to re-build it. Just use:

"west build -d <name of build folder>"

This works up until v2.9.1 (or any feature v2.9.X releases)

For NCS v3.0.0 and onwards, you need to use nrfutil to generate these environment scripts.

nrfutil sdk-manager env --as-script --ncs-version v3.0.1

This will give you almost the same as the generated environment script, but just as an output in the terminal. Copy it, and save it in a file called full_environment_v3.0.1.cmd, and save it in the same folder as your other scripts.

Just on the end, add one line:

SET ZEPHYR_BASE=C:\nordic\SDKs\ncs\v3.0.1\zephyr

(but replace the path to your NCS v3.0.1\zephyr)

Best regards,

Edvin

RE: Must toolchain version match SDK version?

Erlend Isachsen — Wed, 04 Jun 2025 14:26:24 GMT

Hi.

I have an older version installed (you can also check my previous nrf-connect-support file for all versions, 7.13.0, device 2.8.8 and sdk-manager 1.2.0).

so I upgraded with nrfutil self-upgrade (to 8.0.0), followed by nrfutil upgrade device. Closed all VSCode windows and opened the new window. Same error when using the flash command. All new related versions are listed in the new support information.

Next I tried to run from command line:

If I open a new terminal with the command "nRF Connect: Create Shell Terminal", and paste the exact same command that fails when pressing the flash button, the build and flash works. Please see attached files for all output.

devzone.nordicsemi.com/.../nrf_2D00_connect_2D00_support_2D00_20250604141758.json devzone.nordicsemi.com/.../vscode_5F00_output_5F00_2_5F00_4_5F00_0_2D00_3.txt

devzone.nordicsemi.com/.../shell_5F00_build_5F00_output.txt

RE: Must toolchain version match SDK version?

Edvin — Mon, 02 Jun 2025 06:48:54 GMT

Do any of you have the old nrfutil installed and in your system path on your computer?

To check, try opening a terminal in windows and type:

"where nrfutil" (on windows, I believe it is "which nrfutil" on mac/linux):

Does it return 0, 1 or several paths?

Also, what does "nrfutil --version" return?

Also, make sure you are on the latest version of "nrfutil device" using "nrfutil upgrade device":

Does that make any difference?

Best regards,

Edvin

RE: Must toolchain version match SDK version?

kreilly — Wed, 28 May 2025 02:07:22 GMT

Pressing the flash button from vscode fails on the build configuration, despite working in the command prompt where the ZEPHYR_BASE variable was set in.

RE: Must toolchain version match SDK version?

Edvin — Mon, 26 May 2025 11:59:29 GMT

Which part? Flashing the build folder generated from the command line in VS Code? Or flashing from the command line?

RE: Must toolchain version match SDK version?

kreilly — Sun, 25 May 2025 12:12:30 GMT

Hi Edvin,

I did attempt this, and it unfortunately fails.

Kieran

RE: Must toolchain version match SDK version?

Edvin — Fri, 23 May 2025 10:29:16 GMT

kreilly and Erlend Isachsen

Kieran and What happens if you try to take the build configuration that you made using the command line, and flash it from VS Code? Same issue? Or does it succeed?

BR,

Edvin

RE: Must toolchain version match SDK version?

kreilly — Fri, 23 May 2025 08:02:20 GMT

Hi Edvin,

Here you are!

devzone.nordicsemi.com/.../nrf_2D00_connect_2D00_support_2D00_20250523075905.json

Sincerely,

Kieran

RE: Must toolchain version match SDK version?

Edvin — Fri, 23 May 2025 07:04:12 GMT

Hello Kireran! Thank you for contributing! I assume the first log is coming from VS Code. Would you mind uploading your "Generate Support Information" as well?

Best Regards,
Edvin

RE: Must toolchain version match SDK version?

kreilly — Fri, 23 May 2025 01:56:08 GMT

Hello Edvin,

Coming from a duplicate ticket here!

I did this with the blinky application.

First re-build from flash returned this:

devzone.nordicsemi.com/.../3326.txt

Here is the build from the command line

devzone.nordicsemi.com/.../2821.txt

When I try to flash and rebuild:

devzone.nordicsemi.com/.../7612.txt

It works!! I didnt have a device connected so the flashing part failed.

To me it looks like the ZEPHYR_BASE variable was set incorrectly?

Just for reference, when running the toolchain list command, it returns:

devzone.nordicsemi.com/.../3482.txt

Not sure how I can get it working in vscode though unfortunately.

Hope this helps in rolling out a fix for vscode!

Sincerely,

Kieran

RE: Must toolchain version match SDK version?

Edvin — Thu, 22 May 2025 12:18:38 GMT

Hello,

We are still looking into this.

Can you please test something for me, using the latest version of the VS Code extension:

Make sure that you have downloaded and installed both NCS v2.4.0 and v2.9.0.

Then delete the build folder so that there are no build folders in the application we are testing. Either do it from windows explorer, or in VS Code using "remove build configuration":

Then, create a new build configuration using "add build configuration", and make sure that you set both SDK version and toolchain version to v2.4.0:

(I didn't have 2.4.0 installed, so showing how to do it for v2.4.1)

Click "Generate and build" on the bottom, and let it finish. Please save the build log.

Then do a minor modification to main.c, to force a rebuild, and click flash in VS Code. Save the build log.

Then, if it didn't finish successfully, can you please try the following:

Delete the build folder once more, and open a terminal on your computer. Navigate to the application folder and run the following command:

(if you don't have sdk-manager installed, install it using "nrfutil install sdk-manager")

nrfutil sdk-manager toolchain launch --terminal --ncs-version v2.4.0

It should open a new terminal in the same path. In this new terminal, type:

SET ZEPHYR_BASE=C:\nordic\SDKs\ncs\v2.4.0\zephyr

(but replace the path with the path to your v2.4.0\zephyr folder)

And then use this command to build:

west build -b nrf9160dk_nrf9160_ns -d build

Save the build log

Then, again, do a minor modification, and use this command to flash:

west flash -d build

And save the log.

Are any of the flashing attempts successful? If not, can you please upload all the logs? And if the command line build/flash was successful, can you verify that you have the v2.9.0 toolchain installed using the command:

nrfutil sdk-manager toolchain list

Does this list v2.9.0 as well as v2.4.0?

Best regards,

Edvin

RE: Must toolchain version match SDK version?

Erlend Isachsen — Fri, 16 May 2025 13:25:21 GMT

Sure.

Attached is support logs and new build log for that log. I built this with the nRF Connect Extension 2025.4.186 to keep it the same as my previous post, but the error is there in 2025.5.92 as well.

devzone.nordicsemi.com/.../vscode_5F00_output_5F00_2_5F00_4_5F00_0_2D00_2.txt devzone.nordicsemi.com/.../nrf_2D00_connect_2D00_support_2D00_20250516130642.json

For reference, version 2024.12.55 is the latest version that does work, and that I use for programming daily for this reason. Here is a build log and support log for that if that is useful:

devzone.nordicsemi.com/.../working_5F00_vscode_5F00_output_5F00_2_5F00_4_5F00_0.txt devzone.nordicsemi.com/.../working_5F00_nrf_2D00_connect_2D00_support_2D00_20250516132348.json

RE: Must toolchain version match SDK version?

Edvin — Fri, 16 May 2025 12:16:58 GMT

Can you plesae try to generate support logs and upload it here?

Best regards,

Edvin

RE: Must toolchain version match SDK version?

Erlend Isachsen — Fri, 09 May 2025 10:41:36 GMT

I did another test and reproduced the same error with fresh installation of SDK 2.4.0 and toolchain 2.4.0. All done in VSCode with version 2025.04.186 of the nRF extension:

1. Install SDK 2.4.0.
2. Install toolchain 2.4.0.
3. "Browse samples" -> "2.4.0" -> "HTTP application update sample"
4. Build for nrf9160dk_nrf9160_ns (Build OK, but non-critical python warning/error in configure step).
5. Add one character to the first printk (to force rebuild).
6. Run command "Flash active image to board". - fails

Please see attached log and configuration.

devzone.nordicsemi.com/.../vscode_5F00_output_5F00_2_5F00_4_5F00_0.txt devzone.nordicsemi.com/.../0513_2E00_.vscode_2D00_nrf_2D00_connect.json

RE: Must toolchain version match SDK version?

Erlend Isachsen — Fri, 09 May 2025 09:38:53 GMT

Which version of the nRF Connect extension for VSCode are you referring to? In the latest version, if I click "install new toolchain" I don't see any versions below 2.0.0 (probably since the support was removed for toolchain versions <2.0.0 in 2025.04.106). I'm also unable to select 1.9.1 as toolchain when adding a build configuration in this version.

If I downgrade to 2025.1.127, install new toolchain, select 1.9.1, build, edit code and run "Flash active image to board" I get the same error. See attached log and configuration.

The same problem also happens using sdk v2.5.1 and toolchain 2.5.1 if that is easier to debug in the latest version? I can also try a fresh install (of for instance SDK v2.5.3 and toolchain 2.5.3), install both through VSCode and see if the problem is still there?devzone.nordicsemi.com/.../5141_2E00_.vscode_2D00_nrf_2D00_connect.json

devzone.nordicsemi.com/.../vscode_5F00_output_5F00_2.txt

RE: Must toolchain version match SDK version?

Edvin — Tue, 29 Apr 2025 08:23:11 GMT

Can you please try to click "install new toolchain", and then select the folder icon to select the path to your toolchain:

I note that your .vscode-nrf-connect.json points to "toolchainPath": "c:\\ncs\\toolchains\\v2.0.0"

Try making it point to your v1.9.1 toolchain folder.

Best regards,

Edvin

RE: Must toolchain version match SDK version?

Erlend Isachsen — Wed, 23 Apr 2025 15:06:38 GMT

Hi.

When uninstalling v2.8.0 and 2.9.0 of I specifically used the following command in VSCode:
"nRF Connect: Uninstall Toolchain"

So should be toolchain. Let me know if I should remove SDK as well.

I also see that I didn't provide the best info in terms of what works and what does not work in my original post, sorry for that. If I try to only build the project it finishes successfully, but if I run "Flash to board" or "Erase and flash to board" it fails during re re-building step.

So you might be able to reproduce the problem by:

1. Copy application_update sample from 1.9.1 SDK and common folder in parent directory.
2. Build for nrf9160dk_nrf9160ns (SDK 1.9.1, Toolchain v2.0.0, nRF Connect for VS Code v2025.4.106)
3. Complete build successfully.
4. Edit something some code to trigger a file change.
5. Run: Erase and flash active image to board.

^^This only fails if it has to build and flash in sequence. In my projects, flashing always triggers re-build which is why it is particularly inconvenient. See full attached build log in VSCode below. I have also attached the .vscode-nrf-connect.json for the configuration used. Please let me know if you need anything else.

devzone.nordicsemi.com/.../vscode_5F00_output.txt devzone.nordicsemi.com/.../.vscode_2D00_nrf_2D00_connect.json

RE: Must toolchain version match SDK version?

Edvin — Wed, 23 Apr 2025 12:37:41 GMT

I believe you are still talking about installing and uninstalling the SDKs v2.8.0 and v2.9.0. Did you also remove/uninstall the toolchains?

RE: Must toolchain version match SDK version?

Erlend Isachsen — Tue, 22 Apr 2025 11:57:42 GMT

Hi. Apologies for the delay, I was out of office for Easter.

I can confirm that I'm using VS Code for building my application.I have not tried to build from the command line.

All my SDKs and toolchains except from 2.9.0 have been installed with the toolchain manager from nRF Connect for desktop (I tried to install 2.9.0 through both VSCode and toolchain manager as described in my original post). In my first test, I tried installing 2.9.0 through VSCode. When I removed 2.8.0, I can't recall how I did it, but since most of the files remained in my file system I believe I did it from VSCode. Only after uninstalling 2.8.0 through VSCode, rebooting my computer and attempting to build through VSCode did I remove the 2.8.0 folder from my file system. 2.9.0 was uninstalled through VSCode only. Please see the attached txt, I tried to describe the installation states in each test there.

I can try to build one of the 1.9.1 samples and send the entire build log, and then test through command line and update nrfutil as soon as I get time to look more into this. I currently have version 7.13.0 of nrfutil installed.

devzone.nordicsemi.com/.../toolchain_5F00_sdk_5F00_versions.txt

RE: Must toolchain version match SDK version?

Edvin — Mon, 14 Apr 2025 13:25:44 GMT

By the way, when you say that you removed the 2.8.0 and 2.9.0. How exactly did you do this? Did you delete the v2.8.0 and v2.9.0 folders? How did you install it in the first place? I guess that a toolchain followed this installation. Did you remove the toolchain as well? (exactly how to do this depends on how you installed the SDK).

Best regards,

Edvin

RE: Must toolchain version match SDK version?

Edvin — Mon, 14 Apr 2025 12:57:26 GMT

Hello,

After the upgrade, (in your current state) can you please send the entire build log? Including the build log that is attached at the very beginning?

And can you confirm that you are building the v1.9.1 application via VS Code?

Have you tried using command line? There is a file in the SDK that you can call from any command terminal:

v1.9.1\toolchain\cmd\env.cmd, which will set up the toolchain in that command terminal. Then you can use "west build -b <board_name> -d <build folder name> <path to application directory>". Does that manage to build? Mostly for debugging purposes. I am trying to understand why it fails.

Also, do you have nrfutil installed (nb: new version)? If not, can you please install it, and then call these commands:

nrfutil self-upgrade

nrfutil upgrade

nrfutil self-upgrade

nrfutil upgrade

nrfutil install device

And see if that changes anything.

Best regards,

Edvin

RE: Must toolchain version match SDK version?

Erlend Isachsen — Fri, 11 Apr 2025 15:24:44 GMT

Hi. Thank you for the suggestions, although it didn't seem to change anything.

I tried to install 2.9.0, after which 2.8.0 and 2.9.0 worked but not 1.9.1 as before. Then, I tried to reboot my computer and ended up with the same result. Next, I uninstalled 2.8.0. As before, 2.9.0 worked but not 1.9.1. Restarted by computer again and still the same result. I installed and uninstalled the toolchain versions with the commands in VSCode.

After that, I checked my C:/ncs folder to see that 2.8.0 was still there, and I did not find 2.9.0. So I took the extra step to delete 2.8.0 in my file explorer, uninstall 2.9.0 in VSCode, install 2.9.0 in the toolchain manager and restart my computer. Still the same error as far as I can tell.

On a separate note, I checked my nRF Connect for VS Code extension version (2025.1.127) and found I did not have the april update (which I believe was released today, after my original question?). I see this issue is addressed in this update since it prompts me that support for 1.x.x toolchains is discontinued. It also states "If you are working with the nRF Connect SDK v1.x, select the nRF Connect SDK Toolchain v2.0.0 for your configuration". So I guess the intended strategy is to install toolchain version 2.0.0 and use that for my applications in 1.x.

So I tried this in nRF Connect for VS Code v2025.4.106, but flashing with toolchian verison 2.0.0 does not work either. Without comparing the errors line by line, the error in 2.0.0 appears to be the same as in 1.9.1.

RE: Must toolchain version match SDK version?

Edvin — Fri, 11 Apr 2025 13:15:53 GMT

Hello,

Yes. This is actually a bug. I don't recall the details (but I will dig it up if we can't quickly solve this). Can you please try to install v2.9.0 as well? And if the issue doesn't go away, can you uninstall v2.8.0 (and keep v2.9.0)? Does that change anything?

Best regards,

Edvin