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Microsoft Planning To Automate WinSxS Cleanup in Windows 8.1

• By Kurt Mackie
• 03/07/2014

Microsoft is planning to improve its Component Store Cleanup utility in Windows 8.1.

A future Windows 8.1 release will add the ability to carry out "deep clean operations without requiring a reboot," according to a Microsoft blog post. The blog post is dated March 6, but it contains reader comments oddly back-dated to February. The post is the beginning of a four-part series by Microsoft on Windows servicing and the somewhat obscure WinSxS folder, which stores Windows components. These components accumulate in WinSxS folders with each Windows update release, stumping IT pros as to why presumably useless old files are left to pile up.

In addition to enabling Component Store Cleanup without reboots, Microsoft is planning to automate the cleanup process for Windows 8.1 end users as part of a scheduled "scavenging" maintenance task. When that functionality is enabled, the Component Store Cleanup utility will automatically restore disk space that was hogged by "superseded" Windows components. The cleanup process will be timed to run every week, which "ensures that scavenging and deep clean processing happens relatively quickly after patches are released on patch Tuesday," according to Microsoft's announcement.

Microsoft offered no indication when it would roll out these two enhancements to the Component Store Cleanup utility. Windows 8.1 systems currently include a reporting tool that shows the size of a WinSxS store as well as the Component Store Cleanup tool. However the cleanup tool has to be invoked manually, at present, to carry out such operations.

Part of the post is devoted to explaining WinSxS folders and why its contents take up so much space on systems. It's been a recurring question in Microsoft's forums for years.

Microsoft apparently leaves old Windows component files in the WinSxS folder by design, according to its explanation posted back in 2008. The present WinSxS component storage system started with Windows Vista, replacing an older file-based method that relied on .INF files. The older .INF file-based approach was problematic because it required shipping an UPDATE.EXE engine with each distribution.

With the WinSxS approach, the WinSxS folder contains the only complete copy of Windows. The components in the folder get used when needed. It allows features to be installed without having to reference the original installation disks, according to Microsoft's explanation. The old components aren't removed from the WinSxS folder because they become the next "best version of a component" if a component gets uninstalled.

A typical Windows 7 machine might have a WinSxS folder that takes up around 9 GB of space. While that's not an issue so much with Windows 7 systems with inexpensive high-capacity disk drives, it may be more important on Windows 8.1 systems with solid-state drives, which typically offer less storage capacity.

Late last year, Microsoft offered an optional cleanup capability for Windows 7 Service Pack 1 machines called "Windows Update Cleanup." At that time, Microsoft said that there wasn't a comparable cleanup utility available for Windows Server 2008 R2 users.