SharePoint and forms-based authentication problem - Office applications no longer work

Question

We have several sites that use forms-based authentication (FBA) in SharePoint. Many of them work for months without problems. Over the past week or two, we noticed the following behavior for users trying to access a read-only Microsoft Office document (currently validated only with versions of Excel and Word 2007).

The behavior that we see is represented by:

• Document starts to open
• In an Office application, an IE window opens with an FBA login window. There is also a hyperlink in the upper left corner. Skip to main content
• When you click Cancel, the document will open several times
• If you define the site as a trusted IE site, then the Office application login screen works as before (not for most of our sites).
• Officeless files, such as PDF files, do not exhibit this behavior.
• IE non-authenticated browsers (FireFox, Chrome) do not exhibit this behavior.

Does anyone else see this problem? I assume this message was sent by Microsoft, which led to this problem, as we see it on several sites where the code was not updated.

thanks

Answer 1

The problem we encountered was that a policy file was applied on our network, as a result of which the UAC prompt was disabled for Vista / Win 7. When this happens, protected mode is disabled for IE browsers, which caused the problems we saw.

Answer 2

If you want Office Integration to work under forms authentication, you must do the following:

• Enable Central Administration Client Integration for a Form Application
• Use persistent cookies for authentication in an application that supports forms of files
• On the client computer, add the site to trusted sites in IE

If you still see the login screen that opens in the Office document that opens, try the following on the client computer (if Windows 7):

• Go to Control Panel, User Accounts
• Click "Manage Account Control Settings"
• Change the slider to "Never notify"
• Click OK and restart your computer.