Outlook and Windows thinks that Symnatec is not valid

Hi everyone,

I have a weird problem that happened a few days ago. It seems that suddenly Windows stopped to recognize Symantec as a valid antivirus. That creates some weird events in Outlook in particular. We use Endpoint protection and it is working fine. All the PC I've checked are up to date.

I was wondering how to make Symnatec "accepted" by Windows again.

Thanks for your help in advance

Fred