Alert during scan vanishes on scan completion!

Question

Since 15.Mar.2017 I've been getting a yellow triangle warning during every Microsoft Security Essentials scan on my Windows 7 laptop. It always shows up whilst the scan is checking =svchost= and remains on screen for the rest of the scan - Quick or Full. Yet, when the scan completes, I get a green tick on the Home tab and nothing in any of the subdivisions of the History tab.

New false positive, or new malware that is somehow suppressing reports of its existence?

[Added 12.May.2017 : Problem disappeared at next monthly update of Windows 7 and has not been seen again since then.]

Answer 1

Yes, that is probably a false positive since it disappears. A malware infection will always show in the Scanner regardless if it activates at certain times. Microsoft AntiMalware is designed to detect threats regardless of their behavior.

As an alternative, I recommend scanning your PC with AdwCleaner: https://toolslib.net/downloads/viewdownload/1-adwcleaner/

It's an advanced tool that can scan various areas AntiMalware might omit them.