https://devzone.nordicsemi.com/f/nordic-q-a/59449/updating-to-latest-keil-pro-compilerHi, I had some of your example projects which were being evaluated within Keil and SEGGER and now have an issue with Keil after updating to the PRO license. I now get the error &#39;L6218E: Undefined symbol ASSERT (referred from boards.o)&#39; This musten-USTelligent Community 13Tue, 24 Mar 2020 16:58:15 GMThttps://devzone.nordicsemi.com/thread/241442?ContentTypeID=1Tue, 24 Mar 2020 16:58:15 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1afcdb1c-bc69-48ba-898a-3e1c7aa8619bawneil[quote userid="88590" url="~/f/nordic-q-a/59449/updating-to-latest-keil-pro-compiler"]This must be something specific with the pro license[/quote] <p>No - it is a perfectly standard &#39;C&#39; issue.</p> <p>It means exactly what it says - you have used ASSERT in your code, but you have not defined it.</p> <p>(ASSERT is usually a macro)</p> [quote userid="88590" url="~/f/nordic-q-a/59449/updating-to-latest-keil-pro-compiler"]the previous license (32K evaluation) worked fine[/quote] <p>Did you re-install into a different directory, perhaps ?</p> <p>Can you go back to the old version, and use that to see where it was getting its ASSERT definition from ?</p><div style="clear:both;"></div>