I already emailed support about this, but I’m posting the answer here in case I need to find the Google it again someday.
I was trying to export a variable font from Glyphs. It was working until I changed the filename parameter in the VF export to FamilyVariable[wght].ttf, which still worked to export, but with a duplicate file extension, like FamilyVariable[wght].ttf.ttf. However, after that, I could no longer export, and got this vague error message:
Eventually, after restarting my app, my computer, and trying a few versions of Glyphs, I found the solution:
In Finder, I navigated to /Users/stephennixon/Library/Application Support/Glyphs 3/, in which I searched for FamilyVariable. I then deleted all files and folders with that name.
Finally, the VFs exported as usual.
Hope no one else faces this, but if they do, I hope this helps!
Same problem… Yesterday it returned me the same message and I can’t identify any anomalous action by myself. I simply changed the design of a letter and exported as a variable font. Today the situation has changed and the alert I receive is the one shown in the screenshot.
I tried to do manual hinting but the alert comes back. (But now the alert is again “There was a problem writing the file”). For completeness I must specify that there are some letters in the font that contain an overlap of points and where the application shows a red dot (this is essential for me to make the paths compatible between the various masters that I have drawn). I don’t know if it’s an orthodox practice or if it’s not recommended but so far it has never caused any kind of problem and I find it difficult to eliminate all the glyphs that contain this overlap.
