How can I back up open files in Windows 2000 Server, and is the process the same in Windows Server 2003?

I assume you mean, How does NTBackup handle open files? The situation is different for Windows 2003 and Win2K. Let's look first at Win2K. To back up open files, you need to modify the registry. Open your favorite registry editor and go to the HKEY_CURRENT_USER\Software\Microsoft\Ntbackup\Backup Engine\Backup files inuse registry subkey. The data type is REG_SZ, and the default value is 0, which means NTBackup will skip open files. Change the value to 1, which will lock files while they're undergoing backup. One potential problem with this approach is that dynamic files (e.g., WINS database files) will be locked for a period of time. This problem doesn't occur in Windows 2003 because NTBackup uses Microsoft Volume Shadow Copy Service (VSS) to back up files.

VSS creates exact copies of files, including open files. You can place this shadow copy on a hard disk, tape, or other storage device. One good aspect of this approach is that files that change, (e.g., database files) aren't locked but are still included in the backup. You can perform a backup at any time, although periods of minimum activity are always best. Furthermore, you don't need to require users to log off the server during the backup process.