Windows 10 KB5066198 is rolling out as an optional update ahead of the scheduled end-of-life on October 14, 2025. Like the previous few updates, it’s been a dry spell for new features, which is mostly due to the looming end-of-life date. In addition to Windows Update, Microsoft has posted direct download links for KB5066198 offline installers (.msu).
Windows 10 KB5066198 is an optional update, so if you choose to skip, you’ll automatically get all fixes in the next release, which is on October 14, 2025.
Like I mentioned, you don’t get anything new in these optional updates for Windows 10 version 22H2. But KB5066198 does have some noteworthy fixes. For example, a bug that blocked SMB v1 file sharing has now been patched.
Although Microsoft doesn’t want you to use SMB v1, it’s still offered on Windows. Right now, you can choose between SMB 2 and 3 (either is recommended), but if you use SMB v1 and have installed recent updates, such as Windows 10 KB5065429, you won’t be able to share files.
According to Microsoft, users with the SMB 1 protocol couldn’t establish a connection with the shared files and folders after recent updates. But it’s finally patched with today’s KB5066198.
Download Links for Windows 11 KB5066198
Windows 10 KB5066198 Direct Download Links: 32-bit and 64-bit | Microsoft Update Catalog.
What’s new in Windows 10 Build 9045.6396?
In addition to SMB v1 fixes, Microsoft says it patched an issue that botched up Autopilot. Autopilot is for businesses, and for those unaware, organisations use Windows Autopilot to manage and configure the PCs.
However, a bug broke the Windows 10 Extended Security Updates (ESU) Enrollment Status Page when you used Autopilot.
While the bug doesn’t affect consumer edition PCs, it was a headache for system admins.
This is now patched in Windows 10 KB5066198.
Last optional update before Windows 10 end-of-life
KB5066198 is the last optional update for Windows 10. Starting October 14, 2025, even if you sign up for ESU, you won’t get the optional updates. You’ll only get the Patch Tuesday security patches on every second Tuesday of the month.
Microsoft is offering a free one-year subscription to the Extended Security Updates program to Windows 10 users. There’s a small catch that you must have a Microsoft account and subscribe to OneDrive to avail the offer.
However, if you’re in Europe, you won’t be asked to sync Settings to OneDrive. You just need a Microsoft account, and you’re good to go. EEA region users have enjoyed better privacy and control over Windows OS and Microsoft services due to strict DMA rules. It’ll be the case for Windows 10 ESU as well.
In a letter, Euroconsumers, which is a consumer group in the EU, confirmed that it fought with Microsoft, and the company relaxed the Windows 10 ESU rules for consumers in the region.
“We are pleased to learn that Microsoft will provide a no-cost Extended Security Updates (ESU) option for Windows 10 consumer users in the European Economic Area (EEA). We are also glad this option will not require users to back up settings, apps, or credentials, or use Microsoft Rewards,” Euroconsumers noted.
Some believed that they would not need a Microsoft account to subscribe to the ESU program. But Microsoft clarified to Windows Latest that a Microsoft account remains a requirement in the EU. However, you don’t have to sync settings to OneDrive. This is an advantage you get if you’re based outside the EU except the United Kingdom.
Windows Latest is in touch with Microsoft for more details, and we’ll be sharing our hands-on experience with ESU in different regions. Let us know what you want us to test, and we’ll do it for you.
