I would bet that you have some 3rd party add-on installed, as ArchiCAD does not use language files - rather, it has a different version for each language.
Move all CadImage, Cigraph, Encina and other 3rd party add-ons from your Add Ons folder into a temporary folder. Start AC again. Do you get the message? (I imagine not.) Quit, and restore add-ons until you see the message and determine who is causing it ... and then contact that manufacturer if indeed that is the case.
Karl
AC 28 USA and earlier • macOS Sequoia 15.3.1, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB