A few weeks ago, after a period of sluggish operating, an IT guy did a sort out to my machine and ever since it has run like a dream. He told me whilst it's running well, don't fiddle with controls, leave well alone.

About a fortnight ago, I read somewhere that it is possible to change the way a computer runs etc, simply by clicking on something. I foolishly did and ever since, it has been slow on sites that previously gave no trouble. I now have to go and find that recommendation so that I can refer to it and try to undo etc. I think it was on web user.

But, would I be right in thinking that somehow you can turn the system back to how it was running at a given time, ie 1 month/2 months ago?