WPF - Saving font to disk, then instantiating GlyphTypeface for font throws exception. Why?

Question

I am mucking about with WPF glyphs and documents and have run into a null reference exception in the .Net 4 framework.

I extract and save true-type fonts to disk as

Answer 1

My workaround was to simply replace the < Glyphs > with equavalent < TextBlock >s. The couple of pixels difference in layout was not a problem in my case.

Like you noted was the case for you, in my case also it was not a problem in .Net 3.5, but appeared in .Net 4.0.