Opening .hxt/.hxc type of help files available with platform SDK's from MSDN

These type of files which are made available under help folder and are in Microsoft Help 2.0 format can be opened with "dexplore.exe" viewer. This utility is available at "C:\Program Files\Common Files\Microsoft Shared\Help 9". You can open files by typing the following at a command prompt, or associating it with a
desktop shortcut:

<path>\dexplore.exe /helpcol ms-help://<namespace>

where <namespace> is the name under which the help file has been registered on your system. For example:

"C:\Program Files\Common Files\Microsoft Shared\Help\dexplore.exe"
/helpcol ms-help://MS.xxxxx.xx


You can use either Dave Liske's custom Help 2.0 viewer (http://www.mvps.org/htmlhelpcenter/mshelp2/h2view.html) or Rob Chandler's FAR utility (http://helpware.net/FAR/index.html). These both let you display a list of the registered namespaces and choose the one to initialise. FAR Utility will also work for windows vista while h2view will not work. These utilities are replacement for dexplore.exe and will be simple to use.

So by using correct name space and  creating shortcut you can read the help files.
Even if you want you can use Help 2.0 viewer for viewing your help files as per your namespace.
"File->Open Namespace" Then select namespace and initialise.


If you want to create a shortcut just do right mouse click and say create shortcut. Then give the path or above mentioned command ( ""C:\Program Files\Common Files\Microsoft Shared\Help 9\dexplore.exe" /helpcol ms-help://MS.MSDNQTR.v90.en" ) and give the name for shortcut and you are done.