Hiya Fred,
Firstly, confirm that you are using Google Chrome as your browser (web-ferret as you call it)
To do that, go to the 3 horizontal line logo (see picture in my previous post) and hover over it and it should say 'Customize and control Google Chrome'
When you have done that go here -
https://chrome.google.com/webstore/deta ... cddilifddbOnce the page has opened simply click on the big blue button marked 'add to chrome' and that's it job is done.
I would try to resist the temptation to download and install a selection of this type of software as they do tend to cause conflict with anti-virus programs and very often, with each other ... frankly the more you have the slower your browser becomes.
To get your PC back on an even keel again I would suggest that you go to here -
http://eset.co.uk/Home/NOD32-Antivirus and click on the green button and get a fully working 30 day trial of NOD32 - I have been using this AV software for the best part of 10 years and it is simply the best there is out there, Norton, McAfee and all those free ones just pale into insignificance ... well worth the 30 odd quid a year - with a fully licensed product they have a support team that are at the end of a free phone number here in the UK.
Get back to me if you have any further problems
Mike