PlatformIO Community

In VSC Task Window always popping up: "Error: No handler found"


Same here… 1.31 IIRC, and a popup comes up at the bottom right every time that needs to clicked to get rid of it… prior to that it was just a message in the log that went away when it switched to the task terminal.


Can confirm I am also getting this and it’s been bugging me. Doesn’t prevent build from failing. Just every time I build.

Not a confidential project so can provide logs if necessary…


I can also confirm seeing this on the latest VSCode. I’ve seen the “no handler found” error for a couple months but it was non-intrusive, but with the latest update to VSCode it now has the popup which doesn’t get automatically dismissed. This seems to be a bug in the PIO plugin but I haven’t dug into where/what is missing myself.


This is a problem for me, as well.

My setup:

PlatformIO Version: 1.6.0 (2018-12-12)
VSCode Version: 1.31.1 (1.31.1)
macOS Mojave 10.14.2

I have been seeing the “Error: No handler found” errors in the OUTPUT window/tab for quite some time; however the popup window is relatively recent.

Is there any clarity whether this is a native VSCode problem or PIO?


Same problem here, the pop up is annoying


I’ve had that same issue on two debian linux boxes now running VSCode 1.31.1 and PIO Core 3.6.4, and I think it’s related to program AVR / Arduino environments, as my AVR (328p uno and 8mhz bare) projects are giving that error, but my ESP8266 (Arduino also) ones are fine - no errors from them?


Without having tested that it would make sense as my machine at home (AVR/Arduino platform and espressif platform installed) throws those errors as I build for the ESP8266 with Arduino and my machine at work (only espressif) doesn’t (building ESP32 with ESP-IDF)… Both are Win10, VSCode 1.31.1 and PIO Core 3.6.4.


I should probably have been clearer :open_mouth: AVR / Arduino, and ESP8266 Arduino, the latter is not throwing errors, the former is. :wink:


STM32 mbed - also throwing errors.


Same problem here… even if it is harmless, it’s annoying, have to close the popup to read the build results.

PlatformIO Version: 2.0.0 Home 3.6.4 Core
VSCode Version: 1.31.1 (1.31.1)
macOS Mojave 10.14.3
Framework: mbed
Platform: STM32 4.6.0
Board: NUCLEO_F446RE


That worked for me:

Remove all folders from workspace
Remove all extension, and after removing each one, restarting VSCode
Reload extensions
Reopen folders on workspace


This seemed to work for me, as well. Thanks for the suggestion!


Remove (deinstall) extensions, or deactivate?


Seems to work here, too!
Thank you very much for this highly efficient workaround.
I did not deinstall extensions, just disabled/enabled them, including platformio.

[Edit: was not sustainable, error returned after a while]


The error is back :frowning:


Guys, I’m here. How to reproduce this issue? I can’t :frowning: Do you use the latest 1.31.1 release?

What is your list of extensions? Maybe, another extension causes this issue? Could you try to disable all extensions and keep only PlatformIO + C/C++ by Microsoft? This is actually the one extension on the which we depend.


v1.31.1 (user setup) on Windows 10

Still did not find out yet how to reproduce it.
Tried the workaround above, error disappeared, but reappeared after a few build.
Maybe it’s not platformio dependent, but caused by some other VSC extension.


I thought it was only AVR platform related, but one of my ESP8266 projects just started doing this also. I went through and disabled all but the PlatformIO and C/C++ extensions and it went away (VSCODE 1.31.1 + debian linux x64). I selectively turned them back on again, and it seems so far that it is the vscode-icons extension that is triggering the error to come back (robertohuertasm.vscode-icons) - which makes sense as it seemed to rear it’s head vscode-icons had just updated IIRC. My other extensions are markdown related + GitLens + Microsoft Python extension. I’ll update again if it re-surfaces.


Could you try ti disable other extensions and find out which produces this error?


I’m not using this extension (means it is not listed under active extensions), but i do have the error.