Scheduled NTBackup jobs failing after local profiles have been cleaned up

We currently use NTBackup to backup our Active Directory System State, but we discovered through our Telemetry that some of the Backup jobs were failing after some local profiles on the server had been cleaned up, but why?

When you schedule an NTBackup task through NTBackup, the configuration of the job is stored in a .bks file which is stored in C:\Documents and Settings\<currentuser>\Local Settings\Application Data\Microsoft\Windows NT\NTBackup\data and is called in the scheduled task.

This file can be opened by any text editor such as notepad, and could look something like:

C:\
SystemState

When the user profile is cleaned up and removed the .bks file is also removed, and when the job attempts to run from Windows Task Scheduler the job fails.

Resolution:

1. Copy the bks file to a non volatile file location, for arguments sake, I:\System Backups.
2. Change the Command line of your scheduled task to reference the new non volatile location of the bks file. This setting is after the @ parameter eg. "@<unc path to bks file>"