Hello,
You need to set Overwrite Protection Period and Append Period on the media of which the backup to disk folder will be part of. For this, please refer to the below mentioned technotes which talks about OPP and AP :
- An explanation of the "Overwrite Protection Period" and the "Append Period"
http://support.veritas.com/docs/237374
- The basics of Advanced Device and Media Management for Backup Exec for Windows Servers
http://support.veritas.com/docs/192265
Hope this helps you.
Regards
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