When Windows Update is stuck, failing, or silently doing nothing — start here.
Windows Update is a deceptively complex system. Under the surface it involves several services, a download cache, a dozen system DLLs, and a set of enterprise policies. If any piece gets damaged or misconfigured, updates simply stop happening — often silently. This page exposes every repair technique for Windows Update in one place, plus a live diagnostics panel showing the current state of the key pieces.
At the top of the page, TuneBit shows you at a glance:
wuauserv service; should be running.Runs the whole suite in the right order: stops services, clears caches, re-registers DLLs, repairs BITS, resets policies, and restarts services. If you have no idea where to start, click this.
Stops Windows Update services, renames the SoftwareDistribution and catroot2 folders (so Windows recreates them from scratch), and starts the services again. Solves the classic "update just won't finish downloading" problem.
Just the cache cleanup step from "Reset Components." Use this if an update has downloaded as corrupt and keeps trying to reinstall.
Re-registers the dozens of COM components Windows Update relies on. Fixes mysterious errors like 0x80070005 (access denied) when there's no obvious permission issue.
If BITS itself is broken — sometimes the service won't even start — this rebuilds its configuration from defaults.
Clears any group-policy registry keys under WindowsUpdate. If a work laptop has been de-domained or an old tweak is blocking updates, this frees it up.
Asks Windows Update to scan Microsoft's servers right now rather than waiting for its scheduled check. Pair with Open Windows Update to see results immediately.
Opens Microsoft's official Windows Update troubleshooter. It's built into Windows, and sometimes it's enough on its own.
Some big feature updates fail because the Windows Recovery partition is too small or missing. This button checks and rebuilds WinRE so those updates can proceed.