Unable to load sketches to any boards


I have been using the web editor for about a week and it has worked fine, today though it stopped uploading sketches to my Nano, so I reinstalled the plugin. now it generates the error

“Executing command: exec not started”

It does this when I try to upload a sketch to either of my Nanos or My three Unos.

i am running on a laptop and using Chrome browser. I have uninstalled the Arduino SW twice and reinstalled from scratch but it does not seem to make any difference.

As far as I can tell the plugin is running OK, I have used a number of different cables too.

The boards do communicate with the serial monitor still.

Any ideas?


I passed through a similar train of problems with my nano (although the series of errors were somehow different).

@pert advised me (Thank you!) to manually re-select the board to the Atmega328Old flavour. It did work for me.

@andym2233 we were able to reproduce the Nano issue that @falexandru pointed out, about the UNO you are using, are they official boards or clones?

My Arduino Nano is a clone.


There are three flavours of NANO supported you might want to try changing to 328OLD

Also with clones you need to be specific about the COM port you choose first.

Choose the "Board at COM n" which will bring up the board options and from there choose the NANO.
The open box will change slightly and you will see the three flavours of NANO.

Hey @falexandru,
last week we pushed a fix on the Nano Flavours, could you please try again and let us know if you are still encountering this issue?