Windows Security centre reports that my malware protection is off and I cant get it on again. Can anyone help please?
Have you rebooted thrice since the install?
No. Should I? I see that when the Avast icon is turning there is a change. Instead of doing the full rotation in orange, it does half a rotation and the turns to a blue circle with a white ring inside. Also Windows security tells me that there are multiple problems with my security.
Yes. It takes a few reboots to fix the issue.
Have amended my post above but will try another couple of reboots! 
+1
Reason is, sometimes a new file does not get registered properly by Windows. A reboot will allow the old file to be removed whilst it is not in use, and the new one will be properly put in place. Which file that may be, IDNK. Until that is done, Security Center will report an error.
I assume avast! reports it is active and protecting your system? If so, then you have active real-time protection despite what Security Center says.
[EDIT:] Orange/blue color indicates avast! is actively scanning atm. Blue is when it is scanning. Version 4.8 avast! had a blue icon, but that never changed color as does this version.
Security Sytem ok now and I understand by the last reply that all is ok. Avast icon only turns when I am actively making a change.
Thanks to both Alikhan and mchain for help given
You’re welcome.