With Windows 10, and Windows 2016 and higher, wuauclt has no effect as the Windows Update process has been rewritten. A new tool has been found, called usoclient - "Update Session Orchestrator". It is completely undocumented and Microsoft state that it shouldn't be used directly on its own. However the commands it supports have been found.
The most basic command that you can use is
Note that the sub commands are just additional text, no / or -.
Furthermore this runs as a regular user, so no elevation is required.
After running that command you will find that the Windows Update window in Settings will start showing that the machine is doing a scan.
Additional switches for this client have been found which allow you to control the behaviour of Windows Update.
As this command is undocumented, some of this is guesswork based on observed behaviour.
|StartScan||The most basic command, used to start a scan|
|StartDownload||This command will download the updates|
|ScanInstallWait||This is a combined Scan and Download, but not (despite the command name) install. Some reports show that it waits approximately three minutes before an additional command can be used.|
|StartInstall||Used to install the updates that have been downloaded. Used after ScanInstallWait|
|ResumeUpdate||Resumes the installation of the updates when the machine is booted up|
|RefreshSettings||Refreshes Settings to see if any changes have been made.|
|RestartDevice||Restarts the Computer to finish installation of updates - however this command may have been disabled in the most recent (1803 and later) versions of Windows|
|StartInteractiveScan||Starts the scan - appears to have the same behaviour as StartScan|
Another Method to Force Update Check
Another method to forice Windows Update to check for updates is to use Powershell:
Copyright Sembee Ltd. 1998 - 2019.
Reproduction of any content on this web site is prohibited without express written consent. Use of this web site is subject to our terms and conditions.
All trademarks and registered trademarks are property of their respective owners. This site is not endorsed or recommended by any company or organisation mentioned within and is to provide guidance only and as such we cannot be held responsible for any consequences of following the advice given.
Sembee Ltd. is registered in England and Wales at 1 Carnegie Road, Newbury, Berkshire, RG14 5DJ.
Registered company number: 4704428. VAT Number GB 904 5603 43.