I am a big fan of Microsoft Security Essentials even though it ranks on the bottom of such programs. I don't get viruses and Essentials does not bug me. I finally gave in and decided to give Avast another try. If it is intrusive, I will go back to Essentials.
Essentials remained installed so I uninstalled it. Defender in Win10 is reported to turn off when Avast is installed.
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