What is wrong with Windows Update and why does it fail so often? This is one of the the most common question Windows users ask and no-one knows, except perhaps Microsoft.
Windows can update perfectly well time after time and then it suddenly stops working. It may not update at all, it might search for updates and never finish searching, it might try to install updates and never stop installing. It just seems to get stuck at some point.
It gets stuck at different places for different people and probably for different reasons.
Sometimes it is a minor problems that is easily fixed, but occasionally it turns out to be more serious, like Windows Update database errors or corruption.
It happened to me recently and it took two weeks to fix. I didn’t work on it full time, but spent an hour or so on three or four occasions. Eventually it started working again and the latest update is now installed.
Here are the things I tried. Eventually they worked for me and they might work for you too. It is aimed at Windows 10 users, but most of them also work with older versions of Windows.
Check for disk errors
The disk can be checked for errors from within Windows, but I prefer the old command prompt version. It seems to find and fix more problems.
Right click the Start button and select Command Prompt (Admin). Alternatively, expand Windows System on the Start menu, right click Command Prompt and select More, Run as administrator.
Check the disk filing system for errors and repair them by entering:
chkdsk c: /f
A message is displayed saying it cannot check the disk right now, but it can be checked next time Windows is started. Press Y to confirm this, then restart Windows.
Check Windows system files
Windows system files may have been deleted or corrupted, so it is recommended that you check they are all present and correct.
Open an admin Command Prompt (as in the previous section), and enter:
When it has finished, enter these two commands. They perform more Windows system file checks.
DISM.exe /Online /Cleanup-image /scanhealth
DISM.exe /Online /Cleanup-image /Restorehealth
Run the troubleshooters
Troubleshooters that fix problems are built into Windows and they can solve some, but not all problems. Open the Control Panel (it’s on the Start menu) and click Troubleshooting (switch to small icons view if you don’t see it).
Click View all and click Background Intelligent Transfer Service. If the troubleshooter finds a problem, let it fix it, then run it again and again until there is are no problems found.
Then Run Windows Update troubleshooter, click Advanced and then click Run as administrator. If it finds any problems, fix them and then run it again and again until it has fixed everything.
This did not fix all the errors for me, but try it and return to it after completing each of the other tasks.
There is more information on Windows troubleshooters here.
Reset Windows Update components
Resetting Windows Update is complicated, so I will leave it to Microsoft. Go to How do I reset Windows Update components? There are many, many steps. Just work through them. As it says, ignore step 4, but do the rest.
Try those troubleshooters again after doing this.
Clean up the disk
A problem with Windows Update may be that it has partially downloaded an update and then got stuck. While those downloaded files are on the disk, Windows Update will not work. Clear them with Disk Cleanup.
Go to the Start menu, Windows administrative tools, Disk Clean-up. It takes a few minutes to scan the disk and then the window appears. Click the button, Clean up system files.
It scans the disk again and then presents a longer list of things to clean. Tick every box and clean everything. Some of the items relate to Windows Update and cleaning them helps to reset Windows Update.
Run those troubleshooters again
It is hard to say what fixed Windows Update on my PC, but I think Disk Clean-up may have helped a lot. Big updates are saved to a hidden folder on the disk and Disk Clean-up deletes it.
If you have Windows.old on the disk, you can try deleting that from Explorer. It might not work because you don’t have permission, but try it anyway.
Could device drivers be causing a problem? An incompatibility could be an issue. Here's how to solve Windows problems with Device manager.
Restart the PC and then go to Windows Update and see if it is working. It started working on my PC on the third attempt.