Are you getting this message when you start RH, or when you try to create a new project/open an existing project? Best practices recommend using c:\projects\\ as your location.
I found this thread:
The most likely option looks to be how many PUBLISH locations are defined for your project. More information is available (and two more threads) on Peter Grainge's site: http://www.grainge.org: Snippet #136.
The first thread offers a couple of other possibilities if Snippet #136 isn't relevent in your situation.
@kirankatekar24 – what are you doing when you receive this message? What help output are you trying to create?