there is an app called xps from xnalara it's a posing studio that outputs .mesh files, the program functions are terrible to use most people are using blender and 3dmax, but I can't stand blender it's backwards compared to using maya, and I would like to ask for a maya 2015 .mesh importer as well. thanksI think this is making it clear that .mesh is not a standard. It sounds like several apps might have a .mesh output format but I am starting to believe that these are all application specific.
So unless we know what application created the .mesh files then it is going to be hard to come up with something that might convert them.
get blender 2.7 and thisi tried importing one into blender on a friends computer but it wouldn't find the file so i dunno how accurate that information really is or if there's some kind of extra step to it :/