QHelpEngine, cannot open qhc file

[hirti]

Hello,

i have an application which contains online help by using QHelpEngine. The help context is shown in a text browser.
I create the help engine by the following code

myHelpEngine = new QHelpEngine("file.qhc");
	if (!myHelpEngine->setupData())
	  emit setError(3, 160, myHelpEngine->error());

myHelpEngine = new QHelpEngine("file.qhc");
	if (!myHelpEngine->setupData())
	  emit setError(3, 160, myHelpEngine->error());

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If I run the applikation on a PC were Qt is installed everything works fine. But if run it on a PC were no Qt is installed, I got the error message "Cannot open collection file: file.qhc".

Could anybody tell me what i have to install in addition, to use QHelpEngine?