I run Win 10 Pro (upgraded from Win7 Pro) & Norton Security (auto-updated this morning) on an HP HPE-210F (Pavilion 64-bit) delivered with Win7. Norton status reports look nominal.
At least twice now, after a recent major Windows 10 update, possibly Creative, I have selected shutdown of my PC from the user login screen (following complete "sign out" from any account), but it has worked for three or four minutes on shutdown before I heard a half minute of unusual high speed roaring from either the PC fan or its hard drive. Then the PC would begin a restart rather than a shutdown.
Is that activity a normal Windows 10 Behavior or an indication of malware?