I am using Stechup 2017 Make, but suddenly i’m unable to use Extension and 3D Warehouse due to security matters, what a nonsense, ITS REALLY FRUSTRATING
Maybe you can download extensions from the internet and install them from sketchup, I haven’t used sketchup make for a while, I used the 2014 version, but Trimble doesn’t support it anymore, they want people to either use the free web version or pay for a pro license if you work with plug-ins since you can’t install them in the feee version.
There are lots of replies to this elsewhere on this forum. In essence 3D warehouse is only directly available for the modern versions from about 2021 onwards but can be accessed through its webpages.
Look here for an explanation and guidance from DaveR on how to get the models from 3D Warehouse…