Defender closes open programs

ainsurance · 19 Oct 2016

Running windows defender when leaving computer.
When return the next day, chrome and outlook have been closed, and
computer is back to login screen.

Because not looking at computer untill following day,
not sure if it is closing the programs at beginning, middle, or end of scan

It also has, at times, totally turned off computer

thanks

dalchina · 22 Oct 2016

You might be able to glean more this way:
Windows Defender — where are the Scan Results?
Some discussion here, but doesn't give a direct solution:
Windows Defender causes computer to reboot. - Microsoft Community