WhyCrashed

.cab · application/vnd.ms-cab-compressed

What is a .cab file?

Windows Cabinet Archive

About the format

A .cab file is a Windows cabinet — Microsoft's own compressed archive format, in continuous service since Windows 95 for shipping the operating system's components. You'll see cabinets inside driver packages (a .cab holding the .inf/.sys/.dll set), Windows Update payloads, and servicing operations: DISM can install update .cab files directly (DISM /Online /Add-Package), which is the standard route for manually applying an update that Windows Update refuses to deliver. Explorer opens cabinets read-only on double-click, and expand.exe extracts them from the command line; creating them takes makecab or third-party tools. Two practical notes: driver .cab bundles from PC vendors (Dell and Lenovo publish them per-model) are the clean way to grab every driver for a machine at once; and because cabinets can be digitally signed, Windows components distributed as .cab carry verifiable signatures — worth checking on any cabinet that arrived from outside official channels before feeding it to DISM.

How to open a .cab file

Windows

  • Explorer (view/extract)
  • expand.exe
  • DISM (install update/driver cabs)
  • 7-Zip

macOS

  • cabextract

Linux

  • cabextract

Is a .cab file dangerous?

A container with system-level uses. Only install .cab packages (via DISM) from Microsoft or your hardware vendor.

Related file types

.msi.zip.sys

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