You have installed the Office Web Apps on your SharePoint 2010 server. Now you are missing the menu entries “View in Browser” and “Edit in Browser”.

You create a new Excel file in Excel 2007 or 2010, upload it and… there are the menu entries… maybe…

This was the situation of my customer yesterday. He tried to open documents in the Office Web Apps after migration from MOSS to SharePoint 2010. Everything seems to work: Word Web App, PowerPoint Web App, OneNote Web App…

I created a new site collection and uploaded a Excel file (XLSX). – The menu entries appeared.

Then I uploaded a document I’ve downloaded before from the migrated site collection. The menu entries were gone… – THEN I REALIZED: To new document was in OpenXML format (Excel 2007, Excel 2010), the migrated documents in native Excel format of Excel 97…2003. Thats the problem: Only OpenXML Excel files can be viewed an edited in the browser!!! – Thats diffrent from Word Web App and PowerPoint Web App.

I’m looking around on the Microsoft web site, but till now I’ve not found an official comment on that. But this seems to be “behavior by design”… Don’t waste as much time as I’ve wasted with that!