B.E. 8.5 “File open failed” error.

Hello,
Has anyone seen the following error before?

“File open failed for SYS:AUTOEXEC.NCF in Server Specific Info object, error 128. It will not be backed up.”

Error only occurs during a full backup.

Background:
Server: Novell 5.1 O/S on a Compaq Proliant serve
Backup Exec: ver 8.5

TIA