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
[HKEY_CLASSES_ROOT\Wow6432Node\CLSID\{F4754C9B-64F5-4B40-8AF4-679732AC0607}\DocObject]
[HKEY_CLASSES_ROOT\Wow6432Node\CLSID\{00020830-0000-0000-C000-000000000046}\DocObject]
[HKEY_CLASSES_ROOT\Wow6432Node\CLSID\{CF4F55F4-8F87-4D47-80BB-5808164BB3F8}\DocObject]
[HKEY_CLASSES_ROOT\Wow6432Node\CLSID\{00021A15-0000-0000-C000-000000000046}\DocObject]
[HKEY_CLASSES_ROOT\Wow6432Node\CLSID\{74B78F3A-C8C8-11D1-BE11-00C04FB6FAF1}\DocObject]