Hi, This keeps popping up in my event viewer on one of my three exchange machines. I have no DNS errors or Active Directory errors in the event log on those machines. When I run a dcdiag, everything returns successful. I don't know what else to look at for the cause of the problem. Any ideas Server 2003 AD, Exchange 2003 Event Type: Error Event Source: MSExchangeDSAccess Event Category: Topology Event ID: 2103 Date: 5/16/2005 Time: 9:25:10 AM User: N/A Computer: MALGENERAL Description: Process MAD.EXE (PID=1500). All Global Catalog Servers in use are not responding: