ERROR CODE -
"Backup failed writing due to the file system: JZ0C0: Connection is already closed".
PLEASE ADVISE.
What is the DB, embedded or SQL? If SQL, what version? Did you have enough drive space?
Moving this thread to the Endpoint Protection forum.
can u check if symantec manager service is started?
If SEPM is working fine I would recommend running Management Server Configuration wizard once.
If Database is corrupted no use backing it up.