UpdateOS

Update OS

Component of Microsoft Windows
Type	update interface
Introduced in	Windows Phone 8

Update OS is a minimal version of the Windows operating system that performs servicing operations for Windows Phone- and Windows Core OS-based system images. It makes use of a minimal version of the Windows component-based servicing stack (CBS) and runs inside of a bootable WIM image, allowing changes to system partitions to be made while they are not in use.

Functionality

Updates are distributed via the Windows Update service as cabinet packages using the following suffixes:

• .spkg, .spku and .spkr - old Windows Phone 8-style SPKG update delivery method
• .cbs, .cbsu and .cbsr - utilizes the modern Windows CBS stack to install feature updates and optional components on-demand, since Windows 10 Mobile

Most internal Windows 10 Mobile self-hosting builds were released to beta testers through the public Windows Update infrastructure, although only if the host device had a specific "super secret registry key" (SSRK) installed. Some builds (such as build 11069) additionally depend on the presence of the Microsoft.Tools.StudyID1510 feature to install. If a build is pushed to a device without it installed, the servicing stack will fail to process the update due to failing dependency checks.

Since the Windows Phone 8 GDR3 update overall progress is additionally reported during update operations. The operating system will attempt to reboot and retry the servicing operation if it encounters an error.

Gallery

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  Update failure