Microsoft Web Apps Compatibility Issue Revealed

Testing has revealed some editing problems associated with documents from older versions of Microsoft Office, when using Office Web Apps

Users of older versions of Microsoft Office are being warned of potential editing problems associated with Microsoft’s Office Web Apps.

Office Web Apps allow access to browser-based versions of Word, PowerPoint, Excel and OneNote. However, testing of the platform’s technical preview by eWEEK has found that documents from older versions of Office, once uploaded to Web Apps, could not be edited online. This could present issues for users wanting to access the technical preview on machines with aging software.

Microsoft is optimising its upcoming Office Web Apps for .docx, .pptx, and .xslx, which will boost the online accessibility of documents uploaded from users’ desktops. But eWEEK has found that documents with .xls and .ppt file extensions could not be edited through the browser, although they could still be viewed and downloaded.

Office Web Apps will be available to subscribers of Windows Live. Nick Simons, Microsoft’s program manager of Office Web Apps, wrote in an Office Web Apps blog posting that the program’s technical preview had been expanded for “a limited time” to a larger pool of users.


Microsoft first launched its limited technical preview of Office Web Apps on 17 September. With the full version due for release in the first half of 2010, the preview provided a very limited degree of functionality: users could view documents with the Word Web App, view and edit documents with the PowerPoint Web App and Excel Web App.

Microsoft executives told eWEEK during the preview launch that a OneNote Web App would be added at a later date, once certain development milestones were reached.

During testing of the technical preview, the results of which can be found in two posts on the Microsoft Watch blog here and here, eWEEK found that much of the Web Apps’ functionality worked as promised. However, Web Apps displayed error messages whenever an attempt was made to online-edit PowerPoint documents with a .ppt file extension, or Excel spreadsheets with an .xls file extension.

By contrast, uploaded files with .pptx and .xslx extensions could be edited online with no issues.

“Office Web Apps support documents created in Office 2003 and later,” a Microsoft spokesperson told eWEEK when asked about the issue. “However, we optimised for editing and saving .docx, .pptx, .xslx formats because of the important features in Open X M L that support long-term document retention, preservation and accessibility, and the overall read/write performance the file format offers.”

While a large number of Microsoft users rely on Office 2003 or later versions for their productivity needs, a subset that utilises older software may be limited in their use of Web Apps, at least in the technical preview. A recent report by research firm Gartner found that 80 percent of commercial machines still run Windows XP, while a separate research note by Deutsche Bank found that the average age of an enterprise PC had reached 6.1 years by 2008.