Windows Defender won't update

c:\windows\system32\svhost.exe\software distribution\download\install\mpas.exe and
c:]windows\software distribution\download\install\mpas.exe are both blocked. How do I unblock and allow?

Try looking for them under D+/advanced/Computer Security Policy and change them to updater/installer

Can’t find them there.

What kind of a block alert do you get then? Is it a firewall alert then?

They are blocked in defense +
Also in firewall events windows operating system is blocked, is that normal?

How are they blocked in Defense+ then-just a log entry? Easiest thing to do at this point is to add an “allow” for them under Windows Operating System in the network policies (look for it under running processes) and again under D+ if you can’t find them.

First thanks for your help. I’ve been unsuccessful in getting Windows Defender to install updates. I am a new user of Comodo–long time Zone alarm user- so if you have time could you start from the beginning, with instructions on how to get Windows Defender to install updates. My system is Windows xpsp2, with avg antivirus and Windows defender. Any help would be appreciated. Thanks