Windows Update Keeps Failing to Install: What to Do About 0x… Errors

A scenario we know by heart from the service desk: the update downloads, the install reaches 100 %, the computer asks for a restart — and afterwards up pops “Undoing changes made to your computer”. Next day, the same thing. In Settings → Windows Update → Update history, red “Install failed” lines keep piling up, each with a code in the form 0x…

The good news: most of these situations can be sorted out at home, without reinstalling and without losing data. You just need to work through it in a sensible order — from the trivia to the heavier calibre.

Short answer: Start with a plain restart and a check of free disk space (error 0x80070070 is simply a full drive). Then the Windows Update troubleshooter, clearing the download cache in the SoftwareDistribution folder, and repairing system files with the DISM and sfc commands. If the same update keeps failing, try installing it manually from the Microsoft Update Catalog. And if updates have been breaking repeatedly for months, that is not bad luck — usually there is a failing drive, a damaged component store, or a system ripe for a reinstall behind it.

Two trivial things first — they fix half the cases

A restart — a real one, not just closing the lid. Windows is often waiting for a previous update to finish and won’t let a new one through until the computer properly restarts. Choose Start → power → Restart (not Shut down — fast startup can carry the system state over even through a shutdown) and let any “Working on updates” screens run their course.

Free space. A large update can easily need 10–20 GB of headroom: the downloaded package, unpacking it, and a backup copy in case of a rollback. When there isn’t enough room, the install fails — typically with code 0x80070070. You can see how much space you have in Settings → System → Storage. If the drive is full, work through our detailed guide on how to free up disk space in Windows 11 — it lays out a safe order of steps from Storage Sense to cleaning up WinSxS, so we won’t repeat it here.

What the 0x… code tells you

You will find the error code in Update history next to the failed item. It isn’t a verdict, more of a signpost — the same code can have several causes, but it narrows down where to look:

Besides the code, note down the KB number as well (e.g. KB5044284) — it will come in handy shortly for the manual install.

The troubleshooter: the first automatic attempt

It sounds like the kind of buck-passing advice you get from a manual, but the troubleshooter really can repair stuck services and a broken cache — precisely the most common causes. You’ll find it in Settings → System → Troubleshoot → Other troubleshooters; next to Windows Update, click Run. On newer Windows 11 builds, the Get Help app opens instead and walks you through the same steps.

Once it finishes, restart and choose Check for updates in Settings → Windows Update. If the error persists, we go deeper.

Clearing the SoftwareDistribution folder

This is the folder Windows downloads updates into before installing them. When something in it gets damaged — an interrupted download, a power cut, antivirus interference — the system keeps trying to install a faulty package over and over. Typical codes: 0x80070002, 0x80070003, 0x8007000d, or a download stuck forever at the same percentage.

The procedure is safe: we don’t delete the folder, we only rename it, and Windows creates a fresh one. Open the Command Prompt as administrator (Start → type “cmd” → Run as administrator) and enter, line by line:

net stop wuauserv
net stop bits
ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
net start wuauserv
net start bits

Then Check for updates again. The update downloads in full once more — on a slow connection you’ll be waiting a while. This step doesn’t touch your documents, photos or programs in any way; the only visible consequence is that the list in Update history may start from a clean slate. Once everything is running, you can delete the SoftwareDistribution.old folder and free up the space.

DISM and sfc: repairing what the install comes from

Updates aren’t installed “into thin air” but on top of the so-called component store — and when that is damaged (codes 0x80073712, 0x800f0831, or simply repeated failures with no clear pattern), no amount of cache clearing will help. There are two built-in tools for that. In a Command Prompt opened as administrator, enter:

DISM /Online /Cleanup-Image /RestoreHealth
sfc /scannow

The first command compares the component store against the original and re-downloads the damaged parts — it needs an internet connection and can easily take 20–40 minutes; don’t panic if it appears “stuck” at 62 %, that’s normal. The second then repairs the system files using the now-healthy store. The order is deliberate: DISM first, then sfc. When it’s done, restart and try the update again.

Manual install from the Microsoft Update Catalog

When one particular update keeps failing, you don’t have to wait for Windows Update to come to its senses. On the catalog.update.microsoft.com website, search for the KB number from Update history, download the package for your architecture (“x64” on ordinary computers) and run the downloaded .msu file. The install runs outside the Windows Update queue and often goes through where the automated route kept failing.

If even the manual install dies with the same code, that’s useful information: the problem isn’t in the download but in the system itself — which brings us to the next chapter.

When it’s the drive or unmet requirements

Installing an update writes thousands of small files all over the drive. A dying drive therefore often gives itself away during updates — the install fails on various codes, the system freezes during it, and more errors appear after the restart. If you can also hear clicking, the computer is slowing down generally, or even copying files fails, stop dealing with updates and start dealing with your data. How to spot bad sectors on a drive and what the symptoms of a failing SSD are we cover separately — in both cases the rule is the same: back up first, repair afterwards.

The second dead end is unmet requirements. A major autumn upgrade to a new version of Windows 11 can end up in an endless loop of attempts and rollbacks on unsupported hardware (typically code 0xC1900101 due to drivers, or incompatibility messages). The same trap awaits computers running Windows 11 via a “workaround” on a machine without TPM 2.0. If your computer is balancing on the edge of the requirements, read what to do now that Windows 10 has ended — there we go through when an upgrade makes sense, when ESU does, and when a new machine does.

When updates break again and again

A system that has been failing to update for months is rarely fixed by another manual trick. Windows 11 has one last built-in rescue for this: in Settings → System → Recovery there is the Fix problems using Windows Update option. It performs an in-place reinstall of the system — files, apps and settings stay, only the system core is replaced. It takes an hour or more, and you need a stable internet connection and power supply.

If even that doesn’t work, or the system has years of upgrades, attempted repairs and accumulated cruft behind it, the honest answer is a clean reinstall. And let’s be frank here: spending an evening on it and risking wiping your own data isn’t everyone’s idea of fun — that’s what we’re here for. Book online; a Windows reinstall including drivers and basic setup costs roughly from CZK 1,500, or from CZK 2,400 with a backup of your data. If you’re not sure whether the system or the drive is to blame, we’ll start with diagnostics — roughly CZK 600 if no repair follows, and covered as part of the job if it does. The full overview is in our price list.

One more thing before any reinstall, including a DIY one: a backup. Not “I’ve got it on the other partition”, but a genuine backup outside the computer.

What not to do

• Don’t disable the Windows Update service permanently. You’d pay for the peace from error messages with security holes — cumulative updates are mostly patches.
• Don’t download “update fixers” from the internet. The useful tools are built in (the troubleshooter, DISM, sfc); anything posing as a miracle fixer is at best pointless and at worst comes bundled with adware.
• Don’t manually delete anything in the WinSxS folder. Unlike SoftwareDistribution, it isn’t a cache but a component warehouse — meddling with it by hand will break the system.
• Don’t put it off forever. A computer without updates is an ever easier target. In a company, where update errors are hanging over several machines at once, it is also a sign of deeper disorder in IT management — which is exactly what a small business IT audit uncovers.

A Windows Update error isn’t a whim but a symptom: of a full drive, a broken cache, damaged components, dying hardware. Work through the steps in the order given in this article — restart and space, the troubleshooter, SoftwareDistribution, DISM with sfc, a manual install from the catalog — and on most computers the updates will start going through. And if your machine keeps resisting, or after a failed update it won’t even start, bring it to our service centre on Viniční in Brno-Židenice so you don’t have to dig into it yourself.