Regular updates are critical to the effectiveness of a virus scanner, and Windows Defender is no exception. However, how this Windows-integrated scanner acquires these vital updates is very different from third-party scanners. Instead of offering an update scheduler, as most other scanners do, Defender relies on Windows 8’s Automatic Updates feature to search for and install virus definitions.
That is all well and good for systems with Automatic Updates enabled, but many people dislike the mandatory reboots that come with this automation, not to mention the lack of choice in which updates are applied. If you are one of the many who prefer greater control, you might well have Automatic Updates disabled so that you can manually choose what is updated and when. The problem is you probably don’t update your system as often as you should update your virus and spyware definitions, so your system is potentially vulnerable.
Windows Defender includes a prominent Update button so you can manually update the scanner without committing to a system update, but really, how often do you actually click that button? Probably not every day and maybe not every week, which is why scheduling regular updates is so important to maintaining an up-to-date virus scanner. However, without a scheduler built into Defender, you will need to set regular updates in Windows 8’s Task Scheduler, which allows updates even if Automatic Updates are disabled.
Press Win-R, type taskschd.msc and click OK to run Task Scheduler.
Open Task Scheduler Library\Microsoft\Windows\Windows Defender in the left pane and click Create Task in the upper right pane.
Enter a descriptive name in the General tab’s Name field and select Windows 8.1 (or your current Windows version) in the Configure For field.
Click the Triggers tab and select the New button.
Select On a Schedule from the top drop-down menu, which should already be selected by default. Click Daily at the left and configure your preferred start time. Make sure Enabled is checked at the bottom and click OK.
Click the Actions tab and select New.
Select Start a Program from the Action drop-down menu, which should be selected by default. Click Browse and double-click MpCmdRun.exe. Alternatively, manually type the path:
“C:\Program Files\Windows Defender\MpCmdRun.exe”
and keep the quotation marks around it; don’t copy and paste the path, because that can sometimes cause problems. Type:
in the Add Arguments field and click OK.
Click OK to finish scheduling the updates.
You can see the newly created scheduler in the top center pane. If you ever want to disable updates, click Disable in the right pane and Enable to re-enable updates.