Script/ font problem:Music Notes in some

Bizarre stuff happens. On some sites the writings are all in "music notes" some other sites only partial. I checked and double checked for viruses= none. For worms it took me several days..without any findings. Since I uses Outlook Express for the 1st time in dec.2002..this stuff happened. I am on intranet. (local)..Is there any one who could help.. I checked Microsoft site..hours and hours=0. Or is it a font problem. I usually fix my own PC for years (tech books etc) This is baffling.. example: I was on www.trendmicro.com, all the sites in impossible to read (music notes).. this is frustrating I want to upgrade my firewall. Greatly appreciate some answer on this... thanks.