1

Have I been mislead by a Microsoft support member here in Sydney who asked me why I was using Avast when Windows Defender was quite adequate? He also said that Avast might be preventing some automatic upgrades of Windows 10.

2

Depends on your browsing habits and the layered approach you’ve taken for your security, for some people Defender is quite adequate combined with other products and others need a solution that covers a broader area within one single product.

The only updates that would be prevented might be signatures for Defender as it would be disabled when any third party AV was installed.