I can´t install Extension “Sandbox” because of an “Invalid Signature”. I have cleared the cache as suggested on Sketchup troubleshooting. It doesn´t seems to the solution.
Why do you need to install Sandbox ?
It’s shipped with SketchUp and auto-loads at startup.
If your Extension Manager’s Loading Policy is set to unrestricted any extension in your plugins folder will load, even if it’s unsigned etc…
If you still get the error please post the full error message [screenshot or Ruby Console text…
I’m thinking you might not have installed SketchUp properly ??
You can repair it as follows [without affecting what’s been installed so far].
Close SketchUp.
Find its installer exe file - usually in your Downloads folder.
Select that exe’s icon, right-click > context-menu > Run as administrator…
In the dialog that will open choose Repair.
When it’s completed restart your computer.
Run SketchUp again and see if there’s any improvement.
Double-clicking an installer’s exe file to ‘Run’ it is not the same thing, even if your user has admin powers. Unpredictable issues can arise, often around permissions, so some files might not be getting properly copied or read as SketchUp loads etc…
Reason why is that when I try to add sandbox using Toolbar, it doesn´t appear as all other tools. Then when looking into extension manager and trying to push INSTALL nothing happens.
If repairing the installation doesn’t work, I’d suggest quitting SketchUp, deleting both the su_sandbox.rb and su_sandbox folder from the Plugins folder, and then restarting SketchUp. The error message suggests that somehow the contents of the extension have been altered, which will invalidate the signature (of course, if you messed around in there and changed something, that will cause the error).