I found this on Google it's worth a try but you didn't say which OS.
1. open your control panel by click start and then control panel.
2. open your fonts cpl applet.
3. right click in a blank space and left click on "install new font."
4. use the folder window in the bottom left and direct it to C:\windows\fonts
5. select all fonts in the top window and tell it to install the fonts.
6. optionally, you can hold down "Y" on your keyboard to answer yes to all questions about replacing fonts.
If you have your fonts windows open behind this, you should see activity as fonts are removed and re-installed.
Update me on whether or not this fixes your issues please. :)