Favourite Icons Grey

Hi, we had a problem with slow wi-fi in the area and I foolishly thought it was my MacBook slowing down. We cleared the history (Safari) and my friend may have done some other things. But now only a few of the coloured favourite icons have returned. I have tried a safe boot but no joy. Also strangely if I create a new icon it won't let me name it and gives it the name it already has, and the new one is grey.