I point out the significant collision between Defender and Avast. After the last Win 10 update, I detected damage to the Avast installation file and the update of the kernel! Avast could not run normally, I was forced to turn off all the Defender features (which after the last update of Winows! Can not be uninstalled) before it can update the kernel. After a relatively short period of time, the problem will be extended to update the viral chest. When you run a component update, you will see a link to establish a connection, but nothing happens. The whole problem is most likely due to the Firewall Defender activity. Turn the switch off completely. Since Avast contains all the functions contained in Defender, it is not necessary to have both programs turned on. If you’re using Winows 10, make sure you do not even have this problem with you.
No such problem here. Defender shuts itself down as soon as you install a third party AV.