The problem with ofxTrueTypeFontUC

I work with openFrameworks 0.8.3 in Visual Studio 2013.
In my project should be displayed labels in Russian, so I use ofxTrueTypeFontUC.
The problem is that after about 6 hours of the program, it begins to generate an error “INVALID FILENAME … loadFontFace (): could not create new face for PTF76F.ttf …” and does not display any inscriptions. I use the font PTF76F.ttf.
Restart the font does not help - again says that the path to the font is incorrect, although the font file is always in the right place, it’s 100%.
By calling the function I reached file freetype.h and functions FT_New_Face, error happens somewhere in it, or even deeper. Dig up more I did not get.
I found a similar topic on the forum, but there was a speech about ios, and the problem was fixed long ago.
Comrades, can you offer any solution?
Thank you.