@sgaist
There does not seem to be any discernible environment-related reason as to why this happens on some systems and not others.

I have created a new bug report https://bugreports.qt.io/projects/QTBUG/issues/QTBUG-78146

Clive

@JonB said in QHelpEngine:

Or, does the code at https://github.com/srish/QtHelpManual/blob/master/main.cpp (a) work and (b) help you?

I tried this and it almost works. Almost because only the root link from the index view is working, then I have to use links from the content view to navigate. Links under the root item (children) are not working from the index view and clicking on them add error messages in output:

QFSFileEngine::open: No file name specified QTextBrowser: No document for qthelp://org.qt-project.examples.simpletextviewer/doc/./openfile.html

When using my own documentation .qhc file, nothing is displayed. So I definitely didn't catch the logic here. I guess I will stay with Doxygen for documentation.

I updated my previous post since I solved part of the issue.

I encountered the same issue, but since QtAssistant displays images without telling it where to find them, how does it manage to find them? It has to be somewhere in the qch file, right?

Yes. It is a correct way but before the help engine can be used, it must be initialized by calling setupData().

QHelpEngine* helpEngine = new QHelpEngine("http://xxx.yyy/zzz/help.qhc", this); helpEngine->setupData();

Read more here:
http://doc.qt.io/qt-4.8/qhelpenginecore.html#details