Windows Insider RS5 build 17666 highlights fix for crashing Windows Explorer and Lock Screen glitches as known issue in release notes

Kareem Anderson

Screenshot of Windows 10 lockscreen

Seems Microsoft’s Windows engineers saved all their exciting news for after the Build 2018 keynotes. After a feature-packed day one and day two keynote presentations regarding new Windows and Microsoft 365 enabled experiences coming to consumers and developers in the near future, the Windows team just pushed live the latest Insider preview 17666 for Fast Ring and Skip Head release.

As with most early rounds of a new Windows 10 update testing, there is almost equal parts features and issues associated with each release. Below are a list of outstanding issues that may give some Insiders pause before downloading this latest build.

Known issues

  • After completing the Windows Mixed Reality First Run experience, OOBE is black. Motion Controllers are also not recognized in exclusive apps. If you need your Mixed Reality experience to be working it is advised you not take this build until these issues are fixed.
  • On resuming from sleep, the desktop may be momentarily visible before the Lock screen displays as expected.
  • When Movies & TV user denies access to its videos library (through the “Let Movies & TV access your videos library?” popup window or through Windows privacy settings), Movies & TV crashes when the user navigates to the “Personal” tab.
  • We’re aware of an issue that causes Narrator to read extra text when invoking Alt + Tab, and we’re working on a fix.
  • If you complete the setup for a Windows Mixed Reality headset on this build, the headset will remain black until it is unplugged and reconnected to the PC.

Known issues for Sets & Office

  • Sets UX for Office Win32 desktop apps is not final.  The experience will be refined over time based on feedback.
  • The top of some Win32 desktop app windows may appear slightly underneath the tab bar when created maximized. To work around the issue, restore and re-maximize the window.
  • Closing one tab may sometimes minimize the entire set.
  • Tiling and cascading windows, including features like “View Side by Side” in Word, will not work for inactive tabs.
  • The Office Visual Basic Editor window will currently be tabbed but is not intended to be in the future.
  • Opening an Office document while the same app has an existing document open may cause an unintended switch to the last active document. This will also happen when closing a sheet in Excel while other sheets remain open.
  • Local files or non-Microsoft cloud files will not be automatically restored, and no error message will be provided to alert the user to that fact.

But it’s not all bad news. There are several fixes that come with build 17666 that may actually push those annoyed with 17661’s stability or performance such as:

General changes, improvements, and fixes for PC

  • We fixed an issue with dll from the previous flight that could result in explorer.exe crashing every few minutes.
  • We fixed an issue resulting in VPN potentially not working after updating to the previous build.
  • We fixed an issue from the previous build where apps may appear to be missing in secondary accounts after receiving app updates from the PC’s primary account.
  • We fixed an issue from the previous flight resulting in a bugcheck with the error IRQ_NOT_LESS_OR_EQUAL in tcpip.sys.
  • We fixed an issue where a border would be visible when you maximized windows in the last few flights.
  • We’ve updated the design of This PC so that there’s no longer space displayed for the cloud files state icon (which isn’t relevant on this page).
  • The snipping toolbar (with WIN + Shift + S) will now follow your desired theme, light or dark.
  • We fixed an issue that could result in the Emoji Panel and the touch keyboard not displaying correctly if invoked immediately after restarting explorer.exe.

So there you have it, a choice between potentially accidentally minimizing all Sets tabs or finally being done with the flashing taskbar as explorer.exe kept crashing.

Happy downloading, Insiders!