Windows 10 build 17639 releases with new improvements

There's a new preview of Windows 10 version 1809 (build 17639) that delivers a slew of Sets improvements — Here's all you need to know.

Windows 10 build 17639
Windows 10 build 17639

Microsoft is now rolling out Windows 10 build 17639 for devices enrolled in the Fast ring using the Skip Ahead option. This new release is a minor update part of the Redstone 5 development, and it brings a number of new features and improvements.

Windows 10 build 17639, according to the company, introduces a bunch of improvements for Sets and Settings app changes.

Alongside the improvements, build 17639 ships with several fixes and known issues that you can check at the Windows blog. In case you missed it, you can read all the changes for Windows 10 build 17634 in this article.

What’s new on Windows 10 build 17639

Here are all the changes Microsoft is making available with this new preview of Windows 10 version 1809 expected to release in October 2018:


In this flight, Sets, the tab experience for apps, documents, and websites, is getting a slew of improvements and tweaks, including:

  • Drag and drop: You can now drag an app tab around within the Set or combine tabbed app windows into Sets.

  • Alt + Tab: It’s now possible to use Alt + Tab keyboard shortcut to circle between open tabs. (If you have multiple Microsoft Edge windows in a Set, only the one most recently accessed will be visible in Alt + Tab.)

  • Sets context menu: If you right-click a tab, you’ll find additional options, including “close other tabs”, “move to new window”, and “close tabs to the right”.

    Sets tab context menu
    Sets tab context menu

Previous Tabs

In the Previous Tabs experience, you’ll find these changes:

  • You can now pick and choose which Previous Tabs you want to restore, instead of only being able to restore all tabs.

    Sets Previous Tabs
    Sets Previous Tabs
  • You can now restore Previous Tabs from any type of activity.

  • When you open a document that previously had tabs, a prompt will appear offering to restore those tabs, and the Previous Tabs button will be in the filled state. If it’s not a document, a prompt will not show automatically, but you’ll know that there are tabs available to restore because the Previous Tabs button will be in the filled state.

  • There’s a new animation when there are no Previous Tabs available to be restored.

File Explorer

As part of the new Set improvements, File Explorer is also getting several new shortcuts:

  • You no longer need to hold the Ctrl key on the new tab page to launch a File Explorer window in a tab.

  • You can now open new tabs using File Explorer menu.

    File Explorer menu new tab option
    File Explorer menu new tab option
  • Right-clicking on a folder, the context menu includes an “Open in new tab” option.

  • A new Ctrl + T keyboard shortcut to open a new tab when a File Explorer window is in focus. This is in addition to Ctrl + N to open a new window, and Ctrl + W to close the window or tab.

Sets settings

In this Redstone 5 flight, Windows 10 is updating the Sets settings page (Settings > System > Multitasking), and in addition to an option to enable and disable the feature, you can decide the Alt + Tab action, and it’s possible to specify which apps don’t use tabs.

Sets settings on Windows 10 version 1809
Sets settings on Windows 10 version 1809

Microsoft also notes that on build 17639, you’ll notice that Sets looks a little more polished, and switching between tabs is a lot smoother.

Additional improvements

Alongside the improvements on Sets, on the Settings app, the Bluetooth & other devices page now display the batter level for supported Bluetooth devices.

Bluetooth battery level status
Bluetooth battery level status

Starting with Windows 10 build 17639, Control Panel no longer includes the settings to adjust brightness, but these settings can already be configured in the Settings app that will eventually replace Control Panel.

Download Windows 10 build 17639

Although there are no ISO files for Windows 10 build 17639, the update is available immediately through the Fast ring with the Skip Ahead option for PCs. This preview build will download and install automatically on your device, but you can always force the update from Settings > Update & security > Windows Update and clicking the Check for updates button.

You can also check out these resources:

About the author

Mauro Huculak is a Windows How-To Expert who started Pureinfotech in 2010 as an independent online publication. He has also been a Windows Central contributor for nearly a decade. Mauro has over 15 years of experience writing comprehensive guides and creating professional videos about Windows and software, including Android and Linux. Before becoming a technology writer, he was an IT administrator for seven years. In total, Mauro has over 21 years of combined experience in technology. Throughout his career, he achieved different professional certifications from Microsoft (MSCA), Cisco (CCNP), VMware (VCP), and CompTIA (A+ and Network+), and he has been recognized as a Microsoft MVP for many years. You can follow him on X (Twitter), YouTube, LinkedIn and Email him at [email protected].