Vista - NTBACKUP failing intermitently

Running Windows Server 2003 R2 Standard 32 Bit SP1.

Have installed hotfix 211474 and still coming with same issue.

Below is the log file i get of the error.


Backup Status
Operation: Backup
Active backup destination: File
Media name: "hjsweb backup.bkf created 25/06/2008 at 3:00 AM"

Volume shadow copy creation: Attempt 1.
Backup (via shadow copy) of "C: "
Backup set #1 on media #1
Backup description: "Set created 22/02/2006 at 8:15 AM"
Media name: "hjsweb backup.bkf created 25/06/2008 at 3:00 AM"

Backup Type: Normal

Backup started on 25/06/2008 at 3:00 AM.
Backup completed on 25/06/2008 at 3:09 AM.
Directories: 1827
Files: 34843
Bytes: 5,894,005,220
Time: 8 minutes and 51 seconds
Backup (via shadow copy) of "System State"
Backup set #2 on media #1
Backup description: "Set created 22/02/2006 at 8:15 AM"
Media name: "hjsweb backup.bkf created 25/06/2008 at 3:00 AM"

Backup Type: Copy

Backup started on 25/06/2008 at 3:12 AM.

Error: The device reported an error on a request to write data to media.
Error reported: Unknown error.
There may be a hardware or media problem.
Please check the system event log for relevant failures.
The operation was ended.
Backup completed on 25/06/2008 at 3:12 AM.
Directories: 2
Files: 0
Bytes: 160,570
Time: 1 second

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The operation did not successfully complete.

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