Couple things you can do, either erase the media (steps below) or mark the media as overwriteable (steps below). Also I would suggest setting up a media set for your jobs that will automate this process (again, steps below). Looks like you may have just taken the default settings for the media sets that does not allow for overwriting media.
Erase media steps:
1. Go to the Devices tab
2. Select the B2D folder you want to erase media from.
3. In the right hand window, select the media to be erased (you can select multiple media by using the control or shift keys)
4. Right click on the media and select erase
5. Click Yes to the prompt
6. Click Run Now
This may take a couple minutes to run, but will erase the media and make it overwritable.
To just mark media as overwritable
1. Go to the Devices tab
2. Select the B2D folder you want to overwrite media from
3. In the right hand window, select the media to be marked as overwritable. (you can select multiple media by using the control and shift keys.
4. Right click on the media and select "Associate with media set"
5. Select Scratch media from the drop down
6. Click either Yes or Yes to all (if more then one item was selected)
Now the media can be overwritten without it being erased. You can also use these steps to move media to different media sets you have defined.
To create custom media sets.
1. Go to the Media tab
2. Right click on "Media Sets" and select New Media Set
3. Give the Media Set a name (anything you want that helps you remember what they are)
4. In the drop down for overwrite protection period select either Hours, Days, Weeks, or Years.
5. Then enter a number in the box next to the drop down for how long you want to keep the media.
6. Repeat steps 4 and 5 for the append period.
7. Click OK
You don't have to do anything with Vault rules since you are using a B2D folder.
Also you might want to review this technote on media management, it's a long read but should give you a better understand of how media management works.
http://seer.support.veritas.com/docs/192265.htm
After you have created your media sets, you can go into the Job options of the jobs and set them to that media set. You can create as many media sets as you like.
Let me know if you have any questions on all of this.
