OT-CFF fonts should not have a 'kern' table. The kerning in OT-CFF fonts is handled by the 'kern' feature found in the 'GPOS' table.

Miguel made a good point.
But whatever FontBook's validation criteria are, both the declaration as "serious error" and "structure and content" are misleading except if the kern table is really built incorrectly.

I turned off the expansion of the class based kerning upon export and FontBook validated the font as correctly formed.

This creates another problem, as some applications still don't support class based kerning. I have passed this information onto FontLab support.

Thank you for the assistance and insight.

JDooley

The OpenType specification does not permit the "kern" table in PostScript-flavored OpenType fonts, though the Apple specification does. But this obviously is not the problem since FontBook permits some OTF fonts with a "kern" table but chokes on others.

FontBook has been known for false-flagging many situations, and this seems like one of them.

I believe this is an Apple problem, not a problem with your font. You might want to install the Apple FontTools from
http://developer.apple.com/textfonts/Fonttools/
and check your font with ftxvalidator, and see what it reports.

Regards,
Adam

Thank you Adam, I will check into that.

Although I agree that it is probably an error with FontBook validation and not FontLab, since users rely so heavily on FontBook, FontLab might want to look into the error or coordinate with Apple on this issue. I doubt that my font is the only one effected.

Thanks again,

Jeremy Dooley
www.insignedesign.com

Jeremy,

as far as I can tell, this problem has been fixed in more recent versions of Mac OS X. I just tested your font in Mac OS X 10.5.6 and FontBook did not complain at all.

Regards,
Adam