Hi again @toma1,
Now that your former system has been upgraded to a new OS, you should know that the old licensed version of SU must be reauthorized officially in order to enable it to work again. AFAIK, This can only be accomplished thru contacting Trimble’s SketchUp Technical Support (which is provided in the link in my previous post to you). The link is repeated here for your convenience. https://help.sketchup.com/en/contact/technical-support. Just click on the link and be sure to fill out the contact info in the form and I am confident that someone will get back to you soon.
Also take note of the fact that SU 8 is not fully compatible with Windows 10 systems as someone has already pointed out, so there is likely to be some noticeable loss of functionality on a Win10 system, if and when the license is restored.