I am the admin of my pc and I definitely did not block any publisher.
Sure you did, nobody except you can do that: when you replied NO to the request to trust an FSDT module (even a while ago, so you forgot doing that), nothing digitally signed by us will run on your system, unless you un-block it manually. It's not possible this setting would change automatically by itself, it requires manual intervention to block and to unblock.
To Undo your action, go to the Control Panel, under "Internet Options", look for the "Content" tab, there should be a "Publishers" button, that will list the software publishers that you trusted, and another tab with untrusted publishers. If you see "Virtuali s.a.s", remove it from both tabs (especially if it's under untrusted)
