WUAUCLT.exe – Windows CMD Command

Windows Update Agent, download new Windows Update files.

Syntax
      wuauclt Options

Options:

   /a or /ResetAuthorization  Initiate an asynchronous background search for applicable updates.
                              If Automatic Updates are disabled, this has no effect.

   /r or /ReportNow           Send all queued reporting events to the server asynchronously.

   /DetectNow                 Initiate detection right away, Query the WSUS server immediately 
                              to see if any new updates are needed.

WSUS uses a cookie on client computers to store computer group membership when client-side targeting is used. By default this cookie expires an hour after WSUS creates it. If you are using client-side targeting and change group membership, use /ResetAuthorization /detectnow to expire the cookie, initiate detection, and have WSUS update computer group membership.

If Windows Update has been blocked, disabled or failing for a long period of time a long history of updates will build up in the archive, this can cause high CPU use. Resetting the client can help with this, but it will take a long time to run Windows Update afterwards.

Preventing Automatic reboots

Run gpedit.msc

Navigate to: Computer Configuration > Administrative Templates > Windows Components > Windows Update

Open this and change the “No auto-restart with logged on users for scheduled automatic updates installations” to ENABLED

In the control panel choose Update and Security > Windows Update.

Click “Check for updates”

Alternatively set this in the registry:

HKLM:\Software\Policies\Microsoft\Windows\WindowsUpdate\AU
NoAutoRebootWithLoggedOnUsers (DWORD=1 to disable automatic reboots)

Examples:

C:\> wuauclt /a /DetectNow

C:\> wuauclt /r /DetectNow