Hi Lon.
IIS is a component of Windows. You'll need to go into your
PC's Control Panel and load this windows component. However you do
not need to have IIS installed for merged help unless you are using
the RoboEngine - it has now been renamed RoboHelp Server BTW.
So what is the difference I hear you ask? RoboHelp is used to
create, compile and publish help output. One of the outputs is
Webhelp and is designed for posting on intranets, websites, etc.
RoboEngine is a separate product that uses the WebHelp Pro output
from RoboHelp to publish to a central server from where users
access the help.
In summary. If all you want to do is output your help to a
user's PC or a website, you do not need RoboEngine (aka RoboHelp
Server). Hope this helps.