Hi,
what exactly have you named your toolchange macro? Mach interprets all macros as lowercase m,
as a consequence Mach may not be running your macro at all but another.
I've seen that message, its included in a manual toolchange macro. You can see it in Mach4Hobby/LuaExamples/Toolchange..
I'm guessing thats where the messagebox is coming from but why is it running?
Craig