VIRTUALI went in the untrusted publisher list because YOU put it there. This happens if, when FSX asks to trust a publisher for the first time, you mistakenly choose not to trust it, so it goes into the Windows Untrusted publishers list and cannot go away until you remove it from there. If you don't remove it, everything made by us will be blocked by Windows.
To fix this, open the Windows Control Panel, select "Internet Options", select the "Content" tab, click the "Publishers" button, go to the "Untrusted Publishers", and remove VIRTUALI from there.