Update on where I am so far.
This is a tricky little thing. I've run most of the cleaning measures on majorgeeks suggested by M Mouse. First good tip was that I found two items on the rogue list that I was able to uninstall via the control panel. Then I downloaded and ran SuperAntiSpyware. Despite the fact that I've been running malwarebytes on a weekly basis SaS found 242 suspect items which I have removed.
Unfortunately the issue is still there, I have also downloaded Combofix which I am about to run. If this has no effect I'll move on to the rootkit versions. Majorgeeks pages are very good, clear instructions and simple to use.
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