@Leticia Hylary Silva Thank you for reaching out to us, As I understand you are looking for details about Microsoft Defender Application Guard.
No, Microsoft Defender Application Guard has not been discontinued.
Microsoft Defender Application Guard is a feature that provides hardware-based isolation for Microsoft Edge to help protect your device from malware and other attacks. When you use Microsoft Defender Application Guard, any website that you visit is opened in a separate, isolated browsing session that is separate from your device's normal browsing session. This helps to prevent malware and other attacks from affecting your device.
If you need documentation on how to use Microsoft Defender Application Guard, Here is a link to the documentation:
Let me know if you have any further questions, feel free to post back.
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