Comment 8 for bug 1709729

Seems to be the same issue reported as bug #1662293 (no solution so far).

The relevant error is likely:
"Fontconfig error: Cannot load default config file"

Could you please check, that
a) the file \inkscape\etc\fonts\fonts.conf exists
b) you do not have any other files named "fonts.conf"
   located elsewhere on your system?

I think I encountered this before but I wasn't able to find the report yet...