Microsoft is pushing out a cumulative OS update (KB3135173) for Windows 10 on PC. As we reported earlier, this is a standard 'Patch Tuesday' update with fixes and optimizations for the Windows 10 desktop operating system and is available to all users.

Those on the Windows Insider program are on the Redstone (RS1) branch and will likely see a different set of OS security fixes and improvements and will be brought up to the same level for patching.

We reported last week that this update should bump the OS build to Windows 10 10586.104 or .105 and after reboot post installation users should be able to verify the version change (type 'Winver' in the search bar to check).

Microsoft has yet to detail what is in this update, but past practices suggest it will be vaguely worded. We'll update this article when the Knowledge Base is posted.

Update: Here is the full changelog as posted by Microsoft

  • Fixed issues with authentication, update installation, and operating system installation.
  • Fixed issue with Microsoft Edge browser caching visited URLs while using InPrivate browsing.
  • Fixed issue that didn't allow simultaneous install of apps from the Windows Store and updates from Windows Update.
  • Fixed issue that delayed the availability of songs added to the Groove Music app in Windows 10 Mobile.
  • Improved security in the Windows kernel.
  • Fixed security issues that could allow remote code execution when malware is run on a target system.
  • Fixed security issues in Microsoft Edge and Internet Explorer 11 that could allow code from a malicious website to be installed and run on a device.
  • Fixed additional issues with the Windows UX, Windows 10 Mobile, Internet Explorer 11, Microsoft Edge, and taskbar.
  • Fixed additional security issues with .NET Framework, Windows Journal, Active Directory Federation Services, NPS Radius Server, kernel-mode drivers, and WebDAV.

For those with a Surface device, there should be no new firmware posted as Microsoft publishes those separately from the Patch Tuesday OS updates. However, we are expecting Microsoft to address current Surface Pro 4 and Surface Book issues in the coming weeks.

There is no word when the .104 update will ship for Windows 10 Mobile, but the referenced changelog obviously mentions it. The update is likely to come in the next few days.

To check for today's update just head into All Settings > Update & security > Windows Update > Check for updates.