Just a quick update to this problem. I have finally found the answer.
Microsoft have pushed out an update for windows defender which conflicts with some 3rd party Antivirus products. We use Trend WFBS here.
The answer for us was to stop windows defender from running via group policy. There is a link to the how to below.
https://success.trendmicro.com/solution/1058514-windows-defender-and-officescan-compatibility