Thanks for that B&t. IŽll have a look and give it a go.
My search also mentioned Avast antivirus which I have used for years in conjunction with WD so I looked there and found this.
Avast 12.2.2276 and Windows Defender (Windows 7)
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on: July 29, 2016, 11:48:38 AM »
It looks like that new Avast version disabled Windows Defender.
Error says that it is disabled by Group Policy (Error Code : 0x800704ec).
In Group Policy I don't see that Windows Defender is disabled.
I can enable it through Registry, but after reboot it is disabled again.
I never had any problems running both Avast and Windows Defender as antispyware.
Thanks again for the pointer.