I would appreciate any advice you can give on the following: When using a web browser like Google I used to get McAfee advice boxes popping up as my cursor ran over the websites listed. These boxes either said there were no known problems with the site or else identified problems reported. This no longer happens. Was this SiteAdvisor and, if so, how can I reintroduce the facility.
It certainly sounds like SiteAdvisor. Is that item present in either Control Panel/Add or Remove Programs or under Internet Explorer Tools/Manage Add-Ons? If it's in the latter make sure that it is enabled then right-click the top toolbar and make sure that SiteAdvisor is checked.