So, after changing the second line of TeXFiles.py from# -*- coding: iso-8859-15 -*- to # -*- coding: iso-8859-1 -*- the error goes away and "TeX Information" works.
I also find this problem, but I do not really know what is going on. I guess 8859-1 is universally available, and we need to install some language package to use 8859-15? Or 8859-15 is not supported by windows at all? Bo