Welcome to the forum.
Yes you must uninstall X5 before installing RH7. Whilst
RoboHelp HTML can work with more than one version, that is not true
of RoboHelp for Word.
There is information on my site about Using RH7 but it is
mostly aimed at RH HTML users.
In the separate article About RH7 there are some links. See
the Before You Install article.
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