This has been an issue that Njevity has been struggling with on new GP 2013 and GP 2015 installs. The confusing part has been that it will occasionally go away. With a lot of help from Daryl Anderson at Microsoft we finally found a work around. First of all, the issue goes away as soon as an application is installed that drops a DLL file in the AddIn folder of the GP program files.
For cases where there are no DLL files in the AddIns folder simply copy the Microsoft.Dynamics.GP.BusinessIntelligence.Homepage.dll
file from the root of the GP installation (example: c:Program Files (x86)Microsoft DynamicsGP2013) to the AddIns sub-folder.