November 2026 Windows Update: 1,235 Fixes and an Outlook Zero-Day, Install It Now

Microsoft released this month's updates on 10 November with 1,235 security fixes, 66 of them rated Critical. One is a flaw in Outlook that criminals are already using. After October's 1,400 it almost looks like a quiet month, but only October's was bigger. Install it tonight if you can.

The Outlook zero-day

Only one this month, but it's aimed at anyone who opens email attachments without thinking twice. Which is most people.

Microsoft only rates it Moderate. I wouldn't read much into that. Phishing emails are already carrying it, and a leaked password hash on a small office network is a proper headache to clean up.

Other flaws worth knowing

• CVE-2026-111309, CVE-2026-110068 and CVE-2026-110043, Outlook. Three Critical remote code execution bugs. Nobody is known to be using them yet, but between these and the zero-day, Outlook is clearly getting attention.
• CVE-2026-118297 and 11 others, Excel. Twelve Critical fixes in Excel alone. Word got four and PowerPoint one. All need you to open a dodgy file.
• CVE-2026-119969, Windows fonts. Critical remote code execution in how Windows handles fonts. Font bugs are nasty because a document or web page can carry the font without you noticing.
• CVE-2026-122194, Microsoft Defender. A Critical flaw in the antivirus itself. Defender updates its own engine separately from Windows Update, so most PCs will be covered already.

Businesses with their own servers have plenty more: Active Directory, Exchange, SMB and TCP/IP all have Critical fixes this month. If there's a server in the back office that nobody has patched since the summer, this is the month to deal with it.

How to install

1. Settings → Windows Update
2. Check for updates
3. Wait 10-30 minutes
4. Restart when prompted, not three days later

USB audio is finally fixed

Microsoft says it isn't aware of any new problems with this update, which makes a change. It also fixes the USB audio bug that has been hanging around since September, where some USB headsets and audio interfaces went silent or showed a Code 10 error in Device Manager. If you gave up and went back to Bluetooth or the laptop speakers, plug the headset back in once this is installed.

October's optional update is rolled into this one too, so the greyed-out Smart App Control switch and the Remote Desktop error 0xC000000D should both be gone on 25H2 and 26H2. A few new bits come with it. You can choose what appears in File Explorer's right-click menu, the AutoPlay box you get when you plug in a USB stick has been redesigned, and the recovery screens have a "Cloud rebuild" option that reinstalls Windows from the internet.

One change to keep an eye on. Microsoft says Memory integrity (Windows Security → Device security → Core isolation) may now switch itself on for PCs that support it. Good for security. But older drivers for printers, scanners and some games' anti-cheat software don't always get on with it, so if a device stops working after this update, that's one of the first places I'd check.

Windows 10

Still getting Extended Security Updates, which are free for home users until October 2027. This month's patch is KB5131096 (build 19045.7846), and it also fixes the error 87 some people got when adding a network printer after October's update. If you haven't enrolled yet, my Windows 10 end of life guide explains how.

If Windows Update itself is broken

A PC that can't update can't protect itself. The usual culprits are low disk space, corrupted update files, or another antivirus clashing with Defender. My common PC problems post covers the first checks, and Windows 11 not getting updates goes through resetting Windows Update properly. If storage is the bottleneck, speeding up a slow Windows 11 PC has that covered. And if you'd rather hand it over to someone, that's what my computer repairs in St Helens are for.

Last month's update stopped some Xbox games signing in with error 0x87DD0005 and broke Wi-Fi on office and school networks, on top of the USB audio problem above. My October update problems post has the fixes, and the October 2026 Windows update post covers what that month patched.

For the full technical breakdown, Bleeping Computer lists every CVE, and their Windows 11 update write-up goes through the new features in more detail.

Mark

Mark has been fixing computers since the late '90s and went self-employed in 2008. Based in St Helens since 2013, he works evenings and weekends from his home in Laffak, doing friendly, affordable repairs for PCs, laptops, and Macs. See reviews on Google