Welcome to the forum.
It's about as big a compatibility issue as they come. X3 was
around long before Office 2003. The first version of RoboHelp to be
compatible with Office 2003 was X5 and you'll have to download a
patch for that. X5 came out first.
You'll need to upgrade RoboHelp or downgrade Word. Subject to
licence issues you can install more than one version of Word but it
is not something I recommend. People have done it but I am sticking
by my vow never to go there again!
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