Unable to process the request.(Via Amol)

Extract from the original post “After the SharePoint administrator has installed, configured, and activated Office Web Apps, end users might receive an error message when they try to view or edit Microsoft Word, Microsoft Excel, Microsoft PowerPoint, or Microsoft OneNote documents in the browser.


These errors might occur for one or more of the following reasons: (Microsoft recommendations)

• The SharePoint administrator has run Office Web Apps Setup, which configures the default open behavior for SharePoint to open Microsoft Word, Excel, PowerPoint, and OneNote documents in the browser by using their associated Web application. However, the SharePoint administrator has not yet started the services, created the service applications, and activated the Office Web Apps feature.
• The Office Web Apps services are not started on the Web front-end server.
• The Office Web Apps service applications and proxies have not been created.
• The Office Web Apps service applications proxies are not associated with the proxy group of the Web application that the site collection belongs to.
• There might be a problem with the permissions for the service account that is used to run the Web application or one of the Office Web Apps services: Excel Calculation Services, PowerPoint Service, or Word Viewing Service. The Web application and service applications must have the appropriate permissions to access the content databases and the configuration database.”

Complete post here.