MsMpEng running all my apps at once on boot


Well-Known Member
Since installing the Windows 10 Anniversary update, booting has been slow and the PC is sluggish for a while. As soon as I could get Task Manager open I saw C: had 100% utilisation. I ran Resource Monitor and saw that MsMpEng apparently had a long list of my installed programs running at the same time. Each was reading roughly 60KB a second. This lasted a minute or so. What's going on?


Windows Forum Team
Staff member
MsMpEng is the Windows Defender service. With the anniversary updates comes cloud analytics to Windows Defender. It may be building a baseline for your system. How long have you had the update installed?

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