Italic font wont install to Windows 10

Version 2.6.2 (1238)

I have a OTF font which Italics won’t install to Windows 10. Uprights install just fine. Running Fontvalidator returns the following errors:

E1316: The macStyle italic bit is clear, but the post table italic angle is nonzero
E2308: The italicAngle is nonzero, but the head.macStyle italic bit is not set

How do I address these issues in Glyphs? I have italic angle set in under metrics values and I have tried exporting with italicAngle custom parameter.

Have you checked the ‘is Italic’ checkbox in the instance?

Details are outlined in the Naming tutorial.

What happens when you install. Which error message do you get?

It took some time to test this again. I generated new files with “is Italic” on and with the latest Glyphs version. Fontvalidator doesn’t give any red warnings anymore, but the fonts still refuse to be installed to Windows 10 Pro x64. The error simply states that they “are not valid font files”.

Most likely a naming issue. This is described in the Naming and Multiple Masters tutorials.