Do you mean, Windows XP to Windows 7?Or Office 2003 to Office 2007? I'm not sure of the answer, but I think we should narrow down the question
Either way, I don't believe X5 will be compatible and work.
If you are going to use Word 2007, you need to upgrade RoboHelp. If you are going to use Windows 7, you should ask for the Ultimate or Pro version. Then you can install the Microsoft Virtual Machine with XP mode and install X5 there. That's how I did it on my own Windows 7 box.
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