I have a Windows 2000 Server (SP4+) running Exchange 2003 (SP2). A Full backup is performed nightly, using NTBackup (Normal backup to disk, located on another server), and most of the time this runs without a problem. Recently, once every 1 to 3 weeks, the Server will hang part way through the backup operation. It completely locks up, no Display, no response to keyboard/mouse, no remote response. The only thing it responds to is Ping of its IP address. I have to force a Power down/up to recover the server. The only evidencein the Logs, shows that the backup had started, then there are no further entries until the server is restart. The Log entries are as follows: NTBACKUP 8000 Begin Backup ESE 210 Full backup of Storage Group started ESE 220 Start backup of "priv1.edb" ESE BACKUP 907 This is where the log entries stop when there is a server hang. Normally, it should be followed by an "ESE 221" entries indicating the end of the backup of "priv1.edb", followed by an "ESE 220" signaling the start of "priv1.stm". On one occassion, I was remotely monitoring the backup on the server, and the remote screen froze when the amount of transferred data reached 9.5GB, which happens to be the actual size of the "priv1.edb" file. I then examined the backup files that were created during the previous failures, and in all cases they were esentially the same size as the "priv1.edb" file. From this it would appear the Server Hang occurs, as the backup is finishing with "priv1.edb" and about to start with "priv1.stm". This has become a serious issue for this site, as it is usually mangaed/maintained remotely, and there is no on-site technical people.