VERIFIED SOLUTION i

Resolve Error when trying to access the help file with MiPro 12.5: The page could not be found!

product affected: MapInfo Pro™

Issue

An error is produced when trying to access the new help files using MapInfo Professional 12.5.

In this particular example, clicking the help menu in the Layer Control dialog produces the following error:
The page could not be found!
qthelp://mapinfo/mapinfo_professional/pro_help/dialogboxes/layercontrolwindow.html
Please be sure that you have all documentation sets installed.

User-added image

Cause

Sometimes, when incremental installations are on the same machine, such errors can occur due to remnants of other files left on the machine.
 

Resolution

UPDATED: September 20, 2017
In windows explorer, go to the following path and delete the files in that folder.  The necessary components will be generated again once the help system is accessed.

C:\Users\<YourUserNameFolder>\AppData\Local\mapinfo_professional12_5\