My 3d warehouse don't work

my 3d warehouse don’t work …what can i do? please give me solutions…advance thanks

One solution would be to update SketchUp to the latest version.
Since 2017 SketchUp no longer uses the browser of the OS, but an internal one (Chromium)

Older versions used Safari on Mac and Explorer on Windows. Those browsers aren’t supported anymore, so you can’t acces the 3D Warehouse from inside SketchUp.

You can still download and explore models through your favorite browser, though.
Download the version that you use(2015?)