I have a problem with my company SharePoint 2010 Enterprise solution. When opening Excel documents from document libraries where they have been added as linked (from another library, in either same web application or the mysite web application), our users get the Open / Save / Cancel dialogue and chose Open. The document opens in Excel 2010 client application and the user makes modifications to the file, and finally wants to save the modified document back to the document library, when they get a pop-up saying that the file on the SharePoint site is write-protected.
I have confirmed that the user has permission.
Am I missing something? Its only a problem with documents in the library that are links to documents in other libraries.