Vista - Backup Failure

I am using Windows Vista Home Premium. When I try to backup and write my
files out to DVD. I receive this message: "An error occurred following
information might help you resolve the error:
Access is denied 0x80070005".

1. Change backup settings. Create a new, full backup in addition to
change settings.

2. Save setting and start backup.

3. Label and insert a blank disk. "name of PC 6/25/07 8:37 AM Disk 1".

4. Disk in Drive is a previous backup disk. (This is the disk I tried to
use in the previous try.)

5. Inserted new DVD.

6. Scanning files to backup.

7. An error occured. The following information might help to resolve the
error. Access is denied 0x80070005.

This does the same everytime I try to do backup. Anu suggestions?


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Don M