I had a problem similar to this, on the clients in question I had to use the command at a cmd prompt echo %logonserver% This tells you which DC the client has authenticated with, if all the clients with this problem have the same logonserver then troubleshoot this DC. Can't remember what exactly the problem was on the DC but found an events in the event viewer which led me to the answer hope this helps On Tue, 12 Oct 2004 15:40:53 +0400, shoeb <shoeb@xxxxxxxxxxxxxxxxxx> wrote: > http://www.MSExchange.org/ > > The clients on outlook 2003 sometime cannot connect to exchange server. > As soon as they open outlook it ask for user name and password. After > many retries it sometimes connect and many times doesn't connect. We > have to reboot the PC or change the IP address, then only the client > connects. This things are happening randomly on any PC. > > Best Regards > > Shoeb > > ------------------------------------------------------ > List Archives: http://www.webelists.com/cgi/lyris.pl?enter=exchangelist > Exchange Newsletters: http://www.msexchange.org/pages/newsletter.asp > Exchange FAQ: http://www.msexchange.org/pages/larticle.asp?type=FAQ > ------------------------------------------------------ > Other Internet Software Marketing Sites: > World of Windows Networking: http://www.windowsnetworking.com > Leading Network Software Directory: http://www.serverfiles.com > No.1 ISA Server Resource Site: http://www.isaserver.org > Windows Security Resource Site: http://www.windowsecurity.com/ > Network Security Library: http://www.secinf.net/ > Windows 2000/NT Fax Solutions: http://www.ntfaxfaq.com > ------------------------------------------------------ > You are currently subscribed to this MSEXchange.org Discussion List as: > graememrobertson@xxxxxxxxx > To unsubscribe visit http://www.webelists.com/cgi/lyris.pl?enter=exchangelist > Report abuse to listadmin@xxxxxxxxxxxxxx >