Microsoft has taken another step against the Meltdown and Spectre vulnerabilities. This week's Patch Tuesday release updates PCs running x86 versions of Windows 7 and 8.1 against Meltdown, meaning that all currently supported Windows releases now include defense against this vulnerability. The update also takes care of the antivirus compatibility check that had blocked previous security updates on Windows 10. The check has been lifted to "expand the breadth of Windows 10 devices offered cumulative Windows security updates, including software protections for Spectre and Meltdown." Microsoft also said it plans to continue blocking security updates on PCs with incompatible antivirus drivers to "avoid any issues."