Why Wuauserv causes high CPU usage and how to fix it?

Many Windows system processes are considered essential for running a safe and fully functioning PC. Wuauserv is arguably one of the most important: this service (aka the Windows Update service) keeps your PC up to date with the latest feature releases and bug fixes.

Like ntoskrnl.exe and other important system services, wuauserv requires priority access to your system resources from time to time. Unfortunately, this does mean that you will occasionally see wuauserv reporting high CPU usage. If that’s the case for you and you’re looking for a solution, here’s what to do.

Why does Wuauserv cause high CPU usage?

The Windows Update service (or wuauserv), as the name suggests, is responsible for keeping your Windows PC up to date. Urgent security and bug fixes, as well as new features and system improvements, will be made available through the Windows Update system.

Windows usually takes care of these updates without you even noticing, although occasionally you need to fix an update stuck. However, if processes related to wuauserv (such as wuauclt.exe) report high CPU usage in the Task Manager for an extended period of time, it could indicate problems with your PC that you need to troubleshoot further.

For most people, this could indicate an update that is currently being installed – you just have to wait for that update. It could also indicate issues with updates not installing properly, but you could also have corrupt system files that are causing services like wuauserv to stop working properly.

If so, you should check and repair your system files or, worst-case scenario, consider: Factory reset Windows 10† Of course, if your PC is struggling, you should consider upgrading your PC to give it more processing power.

Check your Windows Update status

High CPU usage has a root cause – after all, it’s high for a reason. If wuauserv and related processes (such as wuauclt.exe or svchost.exe) report high CPU usage on your PC, Windows Update is running.

The likely answer is that Windows Update is doing what it does best: downloading and installing updates. Some updates (especially larger feature updates) take time to download and install, requiring additional system resources to complete the process. If so, don’t panic.

Allow Windows Update to complete the update process and, when prompted, restart your PC to complete. You can check your Windows Update status (including whether any updates are currently being downloaded or installed) in the Windows Settings menu.

  1. To check, right-click on the Start menu and select Settings
  1. From the menu, select Windows Settings Update & Security Windows Update† Here you can see the current status of the Windows Update service, including whether updates are available, being downloaded, or currently being installed.

If Windows Update is using a significant amount of your system resources without any sign of usual activity (such as downloading or installing updates), then you should continue to investigate a possible solution to the problem using the steps below.

Check and repair your system files

Imagine that your Windows installation is an expensive wagon clock. It may look simple, but underneath it all kinds of gears, levers and fixtures come together to create the system you use.

However, if one of those gears is broken or damaged, the whole system will stop working. In this case, the gears that break are your system files. Corrupt system files cause problems, be it general system instability (including high CPU usage) or more severe BSOD crashes and errors.

The Windows Update service is one of these gears. If you are having problems with Windows Update, check your system files for errors and fix them if they are found. You can do this using the System File Checker utility in Windows PowerShell.

  1. To get started, right click on the Start menu and select Windows PowerShell (administrator)
  1. In the PowerShell window, type /sfc scannow and select enter to execute the command. This will perform an integrity check of your system files, comparing them to a standard Windows image and any corrupt files it finds automatically, but beware of any additional on-screen instructions.

Disable Windows Update Delivery Optimization

If your local network has multiple Windows 10 PCs, you may notice an increase in the CPU usage of the wuauserv service and related processes. This is due to the Delivery Optimization system, which helps to limit the amount of bandwidth used for Windows Update downloads by sharing the files over your network.

If you have one PC that downloads an important update, this update is automatically shared with other Windows PCs on your network using Delivery Optimization. The same system can also be used to provide updates to other Internet-based devices, thanks to the peer-to-peer nature of the system.

This can come at the cost of your available internet bandwidth (including any data caps on your connection), but it can also cause spikes in your CPU usage when the content is shared with other devices. To mitigate this, you can completely stop Delivery Optimization in Windows Settings.

  1. To get started, right click on the Start menu and select Settings
  1. In the Windows Settings menu, select Update & Security Delivery optimization.
  1. Select the Allow downloads from other PCs slider in the Delivery Optimization menu, switch it to the Out position. You can also leave the slider enabled, but choose PCs on my local network below to restrict the sharing of update files to other Windows PCs on your local network.

After you disable Delivery Optimization, restart your PC to make sure the changes take effect.

Check for malware with Microsoft Defender

If your PC is infected with viruses or malware, the impact on your PC can be significant. Stopping Windows Updates is one possible way that a potential malware infection could cause damage, especially since security updates can prevent certain types of malware from taking effect.

If so, you should scan your PC for malware. While third-party tools are available for this, the best method is to run a boot scan of your PC using the built-in Microsoft Defender.

This full-fledged antivirus and antimalware solution can remove the most stubborn malware infections from your PC. However, you can only use Microsoft Defender if you are not already using a third-party antivirus. If so, consider using that utility’s boot scan features as an alternative.

  1. To get started, right click on the Start menu and select Settings
  1. From the Settings menu, select Update & Security Windows Security Open Windows Security
  1. In the Windows Security window, select: Virus & Threat Protection Scan options† A list of additional scanning methods for Microsoft Defender appears below.
  1. Select the Microsoft Defender Offline Scan option listed, then select Scan now to schedule it.
  1. Windows will prompt you to close all open windows, save your work, and prepare to reboot. Select Scan continue.

After a few moments, Windows will reboot and boot into the Microsoft Defender scan menu. Microsoft Defender checks your PC for malware. Follow any additional on-screen instructions to confirm removal, quarantine, or possible fix for infected files.

Stop automatic Windows updates

While it is not possible to completely disable the Windows Update service and prevent updates from installing, you can temporarily stop them. Pausing these updates can help you continue troubleshooting, especially if a specific update is causing issues.

  1. Start by right-clicking the Start menu and selecting: Settings
  1. From the Settings menu, select Update & Security Windows Update. You can choose to pause the Windows Update service for a week by de Pause updates for 7 days choice. Or select Advanced options to choose a longer period.
  1. Use the Pause updates drop-down menu in Advanced options to select a date to resume Windows updates. The change will be applied automatically.

If you defer your updates through the Advanced options menu, you will need to install the missed updates once the date has passed before you can repeat the process.

Keep Windows 10 updated

If the wuauserv service is causing high CPU usage on your PC, it probably indicates deferred system maintenance. Windows Update is part of that process, but if an update seems inconvenient, you may need to stop installing Windows Update to investigate and fix any underlying issues first.

You can also think of keep your device drivers up to date automatically with Windows Update or a third-party app, although certain components (including your graphics card) may require you to manually download the latest drivers. If you’re concerned about outdated software, you can also update your apps automatically.

Leave a Reply

Your email address will not be published.