Well… Long time… But finally a new post!
If You have drank Linux KoolAid, then You can run on problems when You get some CHM file. It is old format and I think it has place where it can live (like many other proprietary data formats):

But still, You can get documentation in such format, chances are high if You are trying to interface some .Net SOAP service. In Linux – no viewer for CHM.
Or rather no standalone viewer. There is solution – CHM Reader addon for Firefox. It is not perfect (no global search), but allows to navigate through that file. Printouts to PDF usually are stripped from hyperlinks, so navigating through 800 pages is reason why PDF printout is not an option…