Normal situation
==============
If the following conditions are met:
- SharePoint sites use form authentication.
- Do not use persistent cookies.
- Click the link in the SharePoint site to open the office document.
In the office dialog box, a form logon page is displayed. You are required to enter the user name and password. The normal interface is as follows:
Problem description
==================
Now the problem arises. In an environment, the Office does not have a pop-up box asking me to enter the user name and password and render the logon page directly in the main form of the Office.
In addition, enter the user name and password, and click the button to log on .:
Solution
==================
Microsoft has already described this problem in kb932118. The solution is to add this site to the Trusted Zone.
Cause explanation
==================
In fact, this is not a Sharepoint issue, but an IE issue. in IE7 and 8, a new function called protected mode is added. IE puts different sites into different security zones. By default, protected mode is enabled in the Internet, Intranet, and restricted zones, and only trusted zones are disabled. the cache and persistent cookies of the sites in the zone with this function enabled will be isolated. after isolation, these sites cannot write files to applications with lower security levels than IE7.ProgramThe cache and persistent cookie of the site in the zone with Protected Mode Enabled are invisible to other programs.
The authentication provider in the SharePoint site has enabled the persistent cookie, and the site is not in the Trusted Zone. therefore, office cannot find such a persistent cookie. the office wants to authentication again, but the authentication provider implemented on the site says it has already given you the persistent cookie, so the Office has to open the authentication page. note that opening is only a rendering, but the logon mechanism behind it cannot work. this explains why the document cannot be opened even if you enter your username and password.
References:
==============
Plan Authentication Settings for Web applications (Windows SharePoint Services)
Http://technet.microsoft.com/en-us/library/cc288081 (office.12). aspx
Forms authentication in SharePoint products and technologies (part 3): Forms authentication vs. Windows Authentication
Http://msdn.microsoft.com/en-us/library/bb977430.aspx
Persistent cookies are not shared between Internet Explorer 7 and office applications in Windows Vista
Http://support.microsoft.com/kb/932118
Definitions and differences between persistent cookies and session cookies
Http://www.cnblogs.com/awpatp/archive/2010/10/24/1859756.html