First introduced over a year ago, Windows Defender Application Guard for Microsoft Edge is finally available in Windows 10 April 2018 Update (version 1803). It’s a security feature that sandboxes Edge at the hardware level using Microsoft’s Hyper-V technology to provide the maximum level of protection from malware and zero-day attacks against Windows. Interestingly, it’s first introduced only to enterprise users but now it’s available for general public.
Enable Windows Defender Application Guard
Open Control Panel, go to Programs and click “Turn Windows features on or off“.
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Check “Windows Defender Application Guard” option and click OK.
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And restart your computer.
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How to use it
Once rebooted, open Microsoft Edge browser and click the … setting menu. You will see a new option called “New Application Guard window” right between “New window” and “New InPrivate window“
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A new Application Guard window opens up. You will be ready to visit any website in the guarded session that is completely isolated in a Hyper-V powered sandbox. Anything bad happening during the session will not affect and do any harm to your Windows 10 system in any way.
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To double-check, you can open Task Manager and check the Details tab, you will notice that there are a couple new processes running under an unrecognized username such as this. That’s the Hyper-V virtual session that powers the Application Guard window you just opened in Edge.
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Because it’s an isolated session, closing the normal Edge window doesn’t result in closing down the Application Guard window. You will need to manually click the X button to exit it.