Open file in its standard application, according to file extension

[Boron]

Hello,
I just wanted to to "start" a html file, expecting it to be displayed in the standard browser (Firefox in my case; may be Internet Explorer or anything else on other systems; my application is restricted to Windows systems for other reasons):

QString command(QCoreApplication::applicationDirPath() + "/Help/index.html" );
bool success = QProcess::startDetached( command );

QString command(QCoreApplication::applicationDirPath() + "/Help/index.html" );
bool success = QProcess::startDetached( command );

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The html file is in the subdirectory "Help" that lies parallel to the executable.

On Windows systems "starting" a file of any type normally starts the application that is linked to the file extension.
When trying to use this behaviour with a QProcess it doesn't seem to work.

Any ideas how I can open a file in its "standard application"?