Hi, there is one user here in our environment and he is connecting to the internet using proxy.pac file. It pops up intermittently for his Domain Credentials every now and then. We have deleted temporary internet files and folders and even tried putting the proxy IP instead of proxy.pac file , still it's popping up intermittently with the credential window. Can anyone please suggest what can be the issue and the troubleshooting steps. Pallab

Hi Pallab, I would like to know if it asks for credential for each URL. How about other users on other computers? If this issue occurs on all clients, you need to check the Authentication Settings. From IE side, check the issue from following methods, make sure there is no Dial-up and Virtual Private network settings in Internet Option, Connections tab. Tools -> Internet Options -> Advanced -> Enable Integrated Windows Authentication (works with Integrated Windows Authentication set on IIS) Tools -> Internet Options-> Security -> Local Intranet > Custom Level > Automatic Logon Click Start -> All Programs -> Accessories -> System Tools -> Internet Explorer (with no add-ons) Perform the clean boot. http://support.microsoft.com/kb/929135 Best Regards, Niki Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi Niki, I checked the first 3 options, they look ok, same as my machine. I haven't done clean boot though, what i have done is i have set the user back to proxy.pac file again instead of explicit proxy IP address under Proxy Server in LAN Settings. I spoke to the user , he is still getting the credential pop up, it's very intermittent, it comes, 3-4 times in a day. Can you please suggest a few more things to try, he is a part of the same proxy group, that other users are and even i am. I don't get the credential pop up at all while browsing.Pallab Chakraborty

Hi, I notice you have not performed clean boot. Please try it and let me know the result. Since the issue only occurs on one user, I suggest changing his password or recreating his user profile to check the result. It also could be profile issue. If the issue persists, please contact server forum to check the issue from server side. http://social.technet.microsoft.com/Forums/en-US/winservergen/threads Best Regards, Niki Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.