Help internal viewer option grayed out. How can I make it enabled?

Hi.
I saw this and I could not do the same.
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=386952&SiteID=1
Do you know how one can make external Help viewer change to Internal Viewer?
Thank you.
[387 byte] By [wathavy] at [2008-1-10]
# 1

Hello, the method introduced in that thread works for me, could you give more information to your problem, especially what do you mean by "could not do the same"?

thanks

rico

BiteQiu-MSFT at 2007-10-3 > top of Msdn Tech,Visual Studio Express Editions,Visual C++ 2005 Express Edition...