In Project Navigator, when I attempt to open the software manuals by going to Help -> Software manuals, or in the CORE Generator software when selecting to view a data sheet for a core, the following errors occur when the tools are unable to locate Adobe Acrobat Reader:
"Could not open Acrobat Reader"
"Could not find Find the PDF viewer"
The executable that is associated with the Windows File Type for the ".pdf" extension points to the default location for Adobe Acrobat. This is what Project Navigator and the CORE Generator software are trying to use.
You can check the setting in Windows Explorer by selecting Tools -> Folder Option -> File Types. Under registered file types, if you go to the PDF extension, make sure that it is set for the correct path and tool. Select the Advanced button and make sure that there is an Action set for "open" and the Application for this action is pointing to the path for "AcroRd32.exe".
In the CORE Generator software, you can also manually specify the path to your PDF Viewer by selecting File -> Preferences.
NOTE: In Project Navigator, the "Use file associations on user documents" preference, under Edit -> Preferences -> ISE General, must be selected or PDF files added to the project will open in the ISE Text Editor. The ISE Text Editor will also be used when a user selects File -> Open and selects a PDF file which is not part of the Project Navigator project.