Under certain conditions which we cannot identify, an Office 2013 32 bit Edition installation on a 64 bit system may miss registry keys to allow for hosting Office Documents in ActiveX controls. This can be confirmed by going in Help – Application Logs to view the full error message. It should be something like System.Runtime.InteropServices.COMException: The associated COM server does not support ActiveX Document embedding.
To resolve this, you have to create a reg file with the content below and merge it in your registry. A restart may be required. As a preliminary step you could open the registry to confirm that the DocObject keys are indeed missing. The keys below are respectively for : Word, Excel, PowerPoint, Visio, and Project.
Windows Registry Editor Version 5.00