Zero-day — All products

Label legend

Security

Contains fixes for security vulnerabilities.

Preview

Optional update with new features and fixes, without new security patches. Its content joins the next Patch Tuesday update.

Out-of-band

Released outside the usual monthly schedule, usually to fix a specific problem.

Cumulative

Includes everything from earlier updates, so the latest one is enough.

Zero-day

Microsoft reports a vulnerability that was already exploited or publicly known when the fix came out.

Windows Insider Preview

A pre-release build for testers, not meant for everyday PCs.

Updated

We revised this page after publishing because Microsoft changed its notes.