hi everyone,i am facing some problem in RPC over HTTP access, i am not able to login , when i check from backend diagnostic logging it gives me NSPI proxy error, below is the error which i got from backend server, we have open below mention ports from frontend to backend and for dcFrontend to backend: 25,110,143,135, and the three ports for RPC over HTTP for information store,NSPI proxy and in SADC to Frontend and backend : 6001,6002,6004Frontend to DC - 88,389,135,1025,1026,389,3268NSPI Proxy failed to connect to Global Catalog

This is an exchange 2007 or Exchange 2003 or Exchange 2010? what´s the OS where Exchange servers are installedCapecolMCSA - MCTS Exchange Server 2007 - 2010 - MCITP Messaging 2010Blog: http://capecol.spaces.live.com/default.aspx

hi,we have exchange 2003 ent server

Hello Jeevan,Please follow the below mentioned KB'sHow to troubleshoot client RPC over HTTP connection issues in Outlook 2003http://support.microsoft.com/kb/827330How to configure RPC over HTTP in Exchange Server 2003http://support.microsoft.com/kb/833401Arun Kumar | MCSE - 2K3 + Messaging | ITIL-F V3

Hi,NSPI Proxy connect the GC from the DSAccess to provide the address book service for the Outlook clients. To diagnose this issue, we need to ensure the GC and DC are avaible under Directory Access in ESM.Please post the error message on the forum from the Event log. Additionally, please try DCdiag Tool to check the DC connection.Dcdiag Overviewhttp://technet2.microsoft.com/WindowsServer/en/library/f7396ad6-0baa-4e66-8d18-17f83c5e4e6c1033.mspx?mfr=trueThanksAllen