Change log for definition version 1.251.906.0 RSS feed icon

This page lists what has changed in the most recent definitions update for Windows Defender Antivirus and Microsoft Security Essentials.

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The following tables list the new and updated definitions for the version you select here. You can choose from the 20 latest updates, and the most recent update is shown by default:

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Definition available date: Sep 13,2017 09:47 PM UTC

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Updated definitions