Alert levels in Microsoft Security Essentials

When Microsoft Security Essentials detects a potential threat, it uses the associated definition file to assign an alert level to the threat. It then applies the default action associated with that threat level.

Alert levels help you choose how to respond to viruses, spyware, and other potentially unwanted software. While Microsoft Security Essentials recommends that you remove all viruses and spyware, not all software that is flagged is malicious or unwanted. The information in this table can help you decide what to do if Microsoft Security Essentials detects potentially unwanted software on your PC.

Alert level
What it means
What to do

Severe

These are widespread or exceptionally malicious programs, similar to viruses or worms, which negatively affect your privacy and the security of your PC, and can damage your PC.

If you're prompted, remove the detected software immediately. Unless you've changed the default settings, Microsoft Security Essentials will attempt to remove malicious software automatically, helping protect your computer from potential infection. (After automatically removing malicious software, Microsoft Security Essentials might also reset some Windows settings, such as your default home page and search provider.)

High

These are programs that might collect personal information and negatively affect your privacy or damage your PC. For example, the program collects information or changes settings, typically without your knowledge or consent.

If you're prompted, remove the detected software immediately. Unless you've changed the default settings, Microsoft Security Essentials will attempt to remove malicious software automatically, helping protect your computer from potential infection. (After automatically removing malicious software, Microsoft Security Essentials might also reset some Windows settings, such as your default home page and search provider.)

Medium

These are programs that might affect your privacy or make changes to your PC that could negatively impact your computing experience. For example, the program collects personal information or changes settings.

Review the alert details to see why the software was detected. If you don't like what the software does or if you don't recognize and trust the publisher, consider blocking or removing the software.

Low

This is potentially unwanted software that might collect information about you or your PC or it might change how your computer works. However, the software is operating in agreement with the Microsoft Software License Terms displayed when you installed the software.

This software is typically benign when it runs on your PC, unless it was installed without your knowledge. If you're not sure whether to allow it, review the alert details, or check to see if you recognize and trust the software publisher.

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