I have been having issues with certain fonts now showing up even though they are installed. Im not sure if its a windows issue or an adobe issue. Recently I am also getting an unknown error as well.
I can't give any direct help, but you might want to search for articles on fonts at Microsoft – Official Home Page
Happening to me too, I install the font, I can use it, but once Photoshop is shut down and reopens it's not there any more. I reinstall it, it says it's there do I want to over write it. It's driving me crazy.
moving to Typekit
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