Issue with web-base application in Single Sign-On

Hi Experts:

     I'm work on a project using SNC/SPNEGO Single Sign-On.

     Followed the configeration manual in help.sap.com, Single Sign On using SAP GUI is successful. But using Browser to access web application, for example webgui, I got the  401 Unauthorized response from browser.

     Could you please give me some advice what cause the issue and how to solve it.

     Thanks a lot.

Lei