After a long time without an update (2016) Microsoft have released a preview of Redstone 4 for HoloLens. The update has many improvements (see my table below) and I will try and do and hands on video soon.

Before you start you need to be aware that this method wipes your HoloLens so if you want to keep you settings you will have to wait until the update rolls out.

How to install Redstone 4 on HoloLens.

First, download the new update from

To install Redstone 4 on HoloLens you need the Windows Devices Recovery Tool, and to opt into the Insider Program on your Hololens:

Launch the Settings app -> Update & Security -> Get Insider Preview builds -> Get started.

Select Restart to restart the device to prepare to install Preview builds and wait until your device is once again booted.

Next you install and run the Windows Device Recovery Tool and connect up your HoloLens to your PC via USB.

After the app reads your config select Manual package selection

Navigate to the folder where you unzipped the update file

Click on Install Software

It will warn you that everything on your HoloLens will deleted, and if you are ok with then click Continue

The update will then install the new version on your HoloLens and when it’s complete it will reboot and you can click Finish.

More info at

Here are the list of changes:

New features in this preview

For all users

Feature Details Instructions
Auto-placement of 2D and 3D content on launch A 2D app launcher or 2D UWP app auto-places in the world at an optimal size and distance when launched instead of requiring the user to place it. If an immersive app uses a 2D app launcher instead of a 3D app launcher, the immersive app will auto-launch from the 2D app launcher same as in RS1.

A 3D app launcher from the Start menu also auto-places in the world. Instead of auto-launching the app, users can then click on the launcher to launch the immersive app. 3D content opened from the Holograms app and from Edge also auto-places in the world.

When opening an app from the Start menu, you will no longer be asked to place it in the world.

If the 2D app/3D app launcher placement is not optimal, you can easily move them using new fluid app manipulations described below. You can also re-position the 2D app launcher/3D content by saying “Move this” and then using gaze to re-position the content.

Fluid app manipulation Move, resize, and rotate 2D and 3D content without having to enter “Adjust” mode. To move a 2D UWP app or 2D app launcher, simply gaze at its app bar and then use the tap + hold + drag gesture. You can move 3D content by gazing anywhere on the object and then using tap + hold + drag.

To resize 2D content, gaze at its corner. The gaze cursor will turn into a resize cursor, and then you can tap + hold + drag to resize. You can also make 2D content taller or wider by looking at its edges and dragging.

To resize 3D content, lift up both your hands into gesture frame, fingers up in the ready position. You’ll see the cursor turn into a state with 2 little hands. Do the tap and hold gesture with both your hands. Moving your hands closer or farther apart you will change the size of the object. Moving your hands forward and backward relative to each other will rotate the object. You can also resize/rotate 2D content this way.

2D app horizontal resize with reflow Make a 2D UWP app wider in aspect ratio to see more app content. For example, making the Mail app wide enough to show the Preview Pane. Simply gaze at the left or right edge of the 2D UWP app to see the resize cursor, then use the tap + hold + drag gesture to resize.
Expanded voice command support You can do more simply using your voice. Try these voice commands:

  • “Go to Start” – Brings up the Start menu or exits an immersive app.
  • “Move this” – Allows you to move an object.
Updated Holograms and Photos apps Updated Holograms app with new holograms. Updated Photos app. You will notice an updated look to the Holograms and Photos apps. The Holograms app includes several new Holograms and a label maker for easier creation of text.
Improved mixed reality capture Hardware shortcut start and end MRC video. Hold Volume Up + Down for 3 seconds to start recording MRC video. Tap both again or use the bloom gesture to end.
Improved audio immersion You can now hear HoloLens better in noisy environments, and experience more lifelike sound from applications as their sound will be obscured by real walls detected by the device. HoloLens finds your space automatically, and no longer requires you to manage or select spaces. If you have problems with holograms around you, you can go to Settings > System > Holograms > Remove nearby holograms. If needed, you can also select Remove all holograms.
File Explorer Move and delete files from within HoloLens. You can use the File Explorer app to move and delete files from within HoloLens.

Tip: If you don’t see any files, the “Recent” filter may be active (clock icon is highlighted in left pane). To fix, select the This Device document icon in the left pane (beneath the clock icon), or open the menu and select This Device.

MTP (Media Transfer Protocol) support Enables your desktop PC to access your libraries (photos, videos, documents) on HoloLens for easy transfer. Similar to other mobile devices, connect your HoloLens to your PC to bring up File Explorer to access your HoloLens libraries (photos, videos, documents) for easy transfer.


  • If you don’t see any files, please ensure you sign in to your HoloLens to enable access to your data.
  • From File Explorer on your PC, you can select Device properties to see Windows Holographic OS version number (firmware version) and device serial number.

Known issue: Renaming HoloLens via File Explorer on your PC is not enabled.

Captive portal network support during setup You can now set up your HoloLens on a guest network at hotels, conference centers, retail shops, or businesses that use captive portal. During setup, select the network, check connect automatically if desired, and enter the network information as prompted.

For developers

Feature Details Instructions
Spatial mapping improvements Quality, simplification, and performance improvements. Spatial mapping mesh will appear cleaner – fewer triangles are required to represent the same level of detail. You may notice changes in triangle density in the scene.
Automatic selection of focus point based on depth buffer Submitting a depth buffer to Windows allows HoloLens to select a focus point automatically to optimize hologram stability. In Unity, go to Edit > Project Settings > Player > Universal Windows Platform tab > XR Settings, expand the Windows Mixed Reality SDK item, and ensure Enable Depth Buffer Sharing is checked. This will be automatically checked for new projects.

For DirectX apps, ensure you call the CommitDirect3D11DepthBuffer method on HolographicRenderingParameters each frame to supply the depth buffer to Windows.

Holographic reprojection modes You can now disable positional reprojection on HoloLens to improve the hologram stability of rigidly body-locked content such as 360-degree video. In Unity, set HolographicSettings.ReprojectionMode to HolographicCameraRenderingParameters.ReprojectionMode to HolographicReprojectionMode.OrientationOnly when all content in view is rigidly body-locked.
App tailoring APIs Windows APIs know more about where your app is running, such as whether the device’s display is transparent (HoloLens) or opaque (immersive headset) and whether a UWP app’s 2D view is showing up in the holographic shell. Unity had previously manually exposed HolographicSettings.IsDisplayOpaque in a way that worked even before this build.

For DirectX apps, you can now access existing APIs like HolographicDisplay.GetDefault().IsOpaque and HolographicApplicationPreview.IsCurrentViewPresentedOnHolographicDisplay on HoloLens as well.

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