I had a font package with afm, pfb, and inf files. When I tried to copy/paste them into c:\windows\fonts on Windows Vista, they would not install. Nor would they install using the “Install Fonts…” options.
These worked fine with XP — I realized that Vista requires a pfm file. And it is not difficult to convert these, though third party software is required. I download the free AfmToPfm software to complete my conversion:
http://www.proximasoftware.com/afmtopfm/
I hope this helps someone in the same situation.