Let's jump right in and have a look at the Offline Help experience in VS 2010.
Important: You must set VS Help mode = local help -- since local help wont work in VS online help mode (which is the default). Actually local help will show (in online mode) for F1 help (3rd party help only).
Set "Help Library Manager" > "Choose online or local help" > "I want to use local help".
To view local help, select VS 2010 help from the Windows Start menu (see above), or run VS 2010 and press F1.
Or run this command via Windows Start > Run...
Note: this is not a browser URL. The ms-xHelp:/// protocol is associated with HelpLibAgent.exe
So here's what we see when we open help (the default experience)...
Help opens in your default browser. The Help URL http://127.0.0.1/ indicates you are viewing local content (not web content).
A small tip: Notice the URL is actually a long list of name=value parameters. The last parameter "embedded=true" stops the side embedded menu from showing. Delete this or set false to make the menu show.
As you see the default experience is very different from previous versions of help. A very brief TOC (like the Loband MSDN website) and the familiar Index is gone.
Why use 3rd party viewers? They give us full TOC and Index, and a DExplore type experience.
At the time of writing the only 3rd party viewer available is H3Viewer.exe. This is a free viewer by Helpware.
In time there will be many other viewers available. Microsoft themselves have a couple nice viewers in the pipeline. These should be available for download soon and possibly become part of VS 2010 SP1.
H3Viewer.exe by Helpware.
Here I have set Google Chrome to be my default viewer for MS Help Viewer 1.0. When I press F1 in VS 2010 Chrome will open even though IE8 is my default browser.
Agent (HelpLibAgent.exe) is part of MS Help Viewer 1.0 and runs in the notification area of your Windows taskbar.
It's purpose is to serve up the Offline content. It does not run in VS Online help mode (3rd party F1 calls is the exception). As you can see the tool tip shows you the local port Agent is listening on. You can find plenty of info on Agent elsewhere in this site.
Note: Agent being a .NET Application takes a few seconds to load into memory first time. Once loaded help topics open very fast.
The last screen of VS Setup invites you to click "Install Documentation" to install VS local help from the DVD. This actually runs the command.
The Help Library Manager (HLM) application (as the name suggests) managers the help library and is also responsible for installing help, and also flipping between online (the default) and local help modes.
Unlike MS Help 2 (where help could be registered at any location on the hard disk), MS Help Viewer 1.0 stores all registered help in one central location.
The first time HLM runs you will be asked where you want to store your Help Library content. You should accept the default location.
Finally the HLM "Install content from disk" page appears. Add the books you want and click Update.
Help packages are copied from the VS Setup DVD to the Help Library and are merged with the existing VS\100* help catalog content.
Merging of help completes quickly (even for 1.1 GB of compressed content). One reason for this is that Microsoft help packages are pre-indexed.
Once you finish installing, you end up on the HLM home page.
Select "Install content from online" to find even more documentation online.
Side Note: In Windows "Programs and Features" ("Add Remove Programs" in XP) you will see VS 2010 Installs lots of stuff.
Just remember that the "Microsoft Visual Studio 2010" item rules them all. It Installs\Uninstalls\Repairs them all. As a general rule you should ignore all other VS components including "Microsoft help Viewer 1.0".