Microsoft announces that its Application Guard will be available to all Microsoft 365 users with supported licenses.
Microsoft announces Application Guard for Microsoft 365
It was in September 2020 when Microsoft announced the arrival of the Application Guard for Office. A tool was created to proactively prevent attacks suffered on our computers. And now, in January 2021, the company has announced that it is available to all Microsoft 365 users with compatible licenses.
The operation of the Application Guard is simple but at the same time effective: Block files downloaded from untrusted sources and that these do not have access to trusted resources when they are opened, by placing the system such documents from untrusted sources in an isolated space.
Documents in secure environments
In this way, Application Guard for Office, or Microsoft Defender Application Guard for Office, makes use of a separate space, a kind of sandbox, to open those documents that come from unsafe sources and thus minimize the threat before they are opened.

Microsoft pointed out that it analyzes each malicious attack using Application Guard, in a way that serves to improve the use of machine learning to defend against threats. Also, it reports that these files are also protected against kernel-based attacks, as the containers are Hyper-V-based.
The use of the Application Guard for Office allows these documents that we open in that sandbox for isolated virtual space, to be edited or printed without having to leave that secure environment. Files that come from unsecured sources, documents blocked by File Block, or those stored in potentially insecure folders or networks.
Application Guard also allows a user to disable protection for a specific file if required. Before that, the document will be scanned with the Secure Documents function if it is enabled. In addition to document protection, Application Guard also monitors the security of e-mails.
To be able to make use of Application Guard, computers must meet some requirements, both hardware, and software:
- CPU: 64-bit CPU, with 4 cores (physical or virtual), virtualization extensions (Intel VT-x OR AMD-V), Core i5 equivalent or higher recommended.
- Physical memory: 8GB RAM
- Hard disk: 10GB free space on the system drive (SSD recommended)
- OS: Windows 10 Enterprise Edition, Client Build version 2004 (20H1) build 19041 or later
- Office: Office Current Channel Build version 2011 16.0.13530.10000 or later
- Update Rollup: Windows 10 Cumulative Monthly Security Update KB4571756
Application Guard works with Word, Excel, and PowerPoint for Microsoft 365 and is a feature that is disabled by default and can be deployed by administrators on endpoint computers running at least Windows 10 Enterprise Edition, version 2004 (20H1) and have the KB4571756 cumulative monthly security update installed.