All users are intermittently being prompted for their network credentials when accessing SDP 7603. Sometimes they are able to auto authenticate and sometimes they are prompted for their credentials. The system autenticates about 85% of the time. The rest of the time users either have to log in with their credentials or close all browser windows and reopen SDP. Sometimes, a user will have more than one IE window open and closing all the IE windows will allow the user to auto authenticate. Other times, users will not have any programs open and they are still prompted for credentials when accessing SDP. Has anyone else had this issue?