Page 692 - Windows 10 May 2019 Update The Missing Manual: The Book That Should Have Been in the Box

Quick scan. Ordinarily, the program scans your PC continuously.

But if you’re feeling a little antsy, you can also trigger a scan
manually, using this button. It tells Windows Security to inspect
the folders that malware usually targets.

Tip

If, after running this scan, Windows feels that you really should run one of the more
thorough scans, it’ll tell you so after it’s finished.

Scan options. There are other kinds of scans, including Full scan
(checks every single file in every single folder, and takes a long
time) and Custom scan (you choose the folders).

Let’s hope you never need the Offline scan. It’s for especially
tough malware, like rootkits (infections so close to the heart of
Windows that normal antivirus software can’t even find it);

usually, Windows lets you know if an Offline scan is necessary.
Your PC shuts down and then enters a special virus-defense mode

that can inspect your copy of Windows without actually running it.
It takes about 15 minutes to clean your copy of Windows; then
your PC restarts normally.

Once you’ve made your choice, hit “Scan now.”

Allowed threats. This page simply lists software that Windows
thought was malware, but that you allowed to run anyway.

Protection history. Defender watches over your PC constantly, as
a barrier against new virus and spyware infections. Each day, the

program auto-downloads new definitions files—behind-the-scenes
updates to its virus database, which keep it up to date with the
latest viruses Microsoft has spotted in the wild.

This screen shows when Defender most recently scanned your PC,
how many of your files it inspected, how many infections it