Please consider the following step to update WebOffice extensions 10.2.
Uninstall of WebOffice extensions
Uninstall the WebOffice extension via Control Panel\Programs\Programs and Features.
Note: If problems occur during uninstall, also consider the notes in chapter Problems with WebOffice extensions 10.2 Uninstall.
Note: During the uninstall process of the WebOffice extensions 10.2 also the ArcGIS 10.2 Engine will be uninstalled. To avoid problems during the uninstall/install process, please ensure, that the ArcGIS 10.2 Engine still exists on the system before uninstalling the WebOffice extensions 10.2.
Note: If you upgrade the WebOffice extensions from 10.2 to 10.2.1 and the ArcGIS Engine is used to register WebOffice extensions 10.2 (distributed server scenario), then check after uninstall of ArcGIS 10.2 Engine whether the registry key (HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ESRI\ArcGIS\RealVersion) still exists. In this case delete this registry key. Only then it is possible to install WebOffice extensions 10.2.1 with ArcGIS Engine successfully.
Installation of the WebOffice extensions
Follow the instructions in chapter Install WebOffice Extensions in order to install the current version of the WebOffice extensions 10.2.
Note: If you install the WebOffice extensions 10.2 please consider, that your specified user of the COM+ services and the SynerGIS WebOffice extensions service have to be re-configured. See chapter Adapt COM+ Applications for more details.