Create a backup directory for storing the scheduled SharePoint backups (e.g. c:\backupsharepoint)
Create Bat File Directory
Create a directory for storing the backup script file (e.g. c:\scriptssharepoint)
Create Bat File
Create a bat file using the code below, modified for your environment. Use UNC paths when using in a server farm environment.
echo Backup Script For Office SharePoint Server 2007
cd \program files\common files\microsoft shared\web server extensions\12\bin
stsadm.exe -o backup -url http://servername -filename c:\backupssharepoint\backupsharepoint.dat -overwrite
Schedule bat file
Schedule the backup to run frequently, during off peak hours.
Open Start > Programs > Accessories > System Tools > Scheduled Tasks
Add a Scheduled Task
Scheduled Task Welcome Screen, Click Next
Click the program you want Windows to run, Click Browse
Select the backupsharepoint.bat file you created (e.g. c:\scriptssharepoint\backupsharepoint.bat)
Name the task, Schedule it (e.g. Daily)
Start Time, Frequency, Start Date
Username and Password (use a domain user account that has proper permissions and non expiring password )
Keep the backup directory secure. Monitor the job to ensure the job is running properly. Perform test restores from the backup files.
Click Here if you need similar instructions for SharePoint Portal Server 2003.