Old extensions

[Anonymous]

Can I somehow use my old extensions in Archicad 21? Some company have their own product-specific extensions, but only for ac19, ac20, is there any possibility?

[Karl Ottenstein]

I assume you mean "add-ons"? All add-ons have to be built (compiled) specifically for each version of AC, as they utilize a variety of common information. So, you cannot simply copy an add-on from AC 20 to AC 21 and expect it to run. The developer would have to recompile it for AC 21.