I get the following issue when trying to publish my website:
Could not generate code to enable one or more web fonts on page 'PingPong | Home'. [Error 400: Font not Available]
However, I did install my webfonts as far as I know (put them manually in the font librabrary). It's a font of Font Spring (see picture attached).
Did you add the web fonts using the Add Web Fonts dialog within Muse?
Is it just this one font that is causing an issue? Or are you having an issue with all self-hosted fonts?
Also, see this article if you haven't done so already