Please download the most current version of the 5.3 message manual.
My edition (october 2005) shows the following explanation:

ANS1468E Backing up Automated System Recovery (ASR) files failed. 
No files will be backed up. 

Explanation: An error occurred while backing up the files needed for
Automated System 
Recovery (ASR). No files were backed up. 

System action: Processing stops. 

User response: Ask your system administrator to check the error log. 
Verify that the Windows account from which you are running this command
has 
administrator authority and try the command again.

HTH
Thomas Rupp