Paul NZ :
Whats no longer certified defender still gets updates. It isnt dead yet. At least it doesnt crash like the rest of them
It no longer has a security certificate, Microsoft even said the software will no longer cover the latest or even all threats. It's like protecting a city with a wall only halfway around it. It's pretty much useless for all but the most basic threats.
If you don't want to install another anti-virus, the least you can do is run a downloadable anti-vrius tool.
Here is a link to such a program
http
/housecall.trendmicro.com/
You might as well turn off windows defender, it's a false sense of security.