I've been getting the following error off and on for two years. Sometimes it works, sometimes it doesn't, currently it never works. I have tried every online solution, closed programs, signed out and in again etc. etc. but to no avail. Two days ago I reinstalled Creative Cloud. All software is up to date. Still no joy. Hoping somebody can help.
Could not generate code to enable one or more web fonts on page 'XXX'. [Error 500]
Could you take a quick look through Troubleshooting Typekit issues reported in Adobe Muse and if none of the reported issues match what you're experiencing, send us the log files requested at the end of that page,
I'm getting the same message today with a site I've published 100x. I didn't see any reported problems on the issue link. Also not seeing the log files requested to send you.