I would have given up weeks ago except others claim this is no problem at all so I stupidly keep trying. mbedcli will build and flash a successful blinky test so I think all is well with it. I have not intricately set up the gnu eabi tool paths inside System Workbench because they seem to be ok and no-one else seems to have needed to, yet it emits errors like make and gcc are not found in path. I can build my own test code with System Workbench, I just can't import and build code from mbedcli export with it. I followed Dan Beckett's sequence here: https://os.mbed.com/questions/85469/Eclipse-CDT-IndexingParser-Issue/#answer16465 Project Explorer shows > [red x] eventOS [mbed-os mbed-os-5.12] > [red x] mbed-os-example-blinky [mbed-os-example-blinky master] It's a nucleo F401RE. What is the trick, how the (shpx) are people doing it? Stefan