I used to include the documentation of software I write, such as
Irrlicht and
irrKlang in the form of
CHM files, a file format by Microsoft consisting of compressed HTML files with an index and table of contents.
The problem with this is that .chm viewers are only natively installed on Windows operating systems, users with Linux or Mac OS X usually have to download some external software to read the documentation. Additionally, it seems that because Microsoft now considers its own file format a security risk and instead of fixing the hole, sometimes the CHM Viewer (aka Internet Explorer) seems to refuse to show the content of those files, and in some cases (from my experience) it cannot even be forced to show the file nevertheless.
That's the reason why I now decided to stop using .chm files and include the .html and .png files directly, in uncompressed form in the SDKs. Anyone today knows how to open .html files and as doxygen now also includes a nice JavaScript based search functionality, the switch should be painless.
To begin with irrKlang, the next release (to be released in the next days) will no longer include .chm files.