By default P6 Professional help is available through OTN. Follow these instructions to install a local copies of P6 Professional help.
Double-click setup.exe in the Client_Applications folder of the physical media or download.
On the Welcome dialog box, click Next.
On the Change, repair, or remove installation dialog box, choose Change.
Expand P6 Professional Common Components.
Expand P6 Professional.
Expand Internationalized PM Help.
Click the name of the language for the help you want to install locally and select Will be installed on local hard drive.
Note: Except for Chinese (Simplified), French, German and Japanese, all of the language selections install English help. In order for the help to work properly, you should select the language that matches the languages in which you use the P6 Professional user interface.