Question : Backup Exec and Overwritable Media

We run full backups every night. On this server it usually takes about 7 1/2 to 8 hours to complete.
For the last 3 days the Backup will start and run for about 5 hours, then get error in event log (event ID_58061) Please insert "overwritable media".
And it will error out every 15 minutes after that. (same error)
I have run these tapes since 08-05-2006, and this is just started this week (monday), three straight days, three different tapes.
We have a 2 week rotation (5 tapes per-week) I have check the settings and they all seem to be set to overwrite, and I reset the media set with the wizard, to make sure something didn't change. (change from 3 days protection to 3 hours)
It is like the tapes are filling up and it is waiting for another tape to be put in...we are using DAT 72 tapes with compression, which I believe that should be 72 gigs (correct me if I'm wrong).
The backup shows 55,500,000,000 to 55,600,000,000 in the bytes counter in backup exec when it stops and errors out (roughly a little over 51gigs). So if I'm reading this correct, there should not be a space problem.
The tapes are all set to overwrite and the Media Set is set to "None" in the Overwrite Protection period, and "None" to the Append Period, with the "Infinite-Allow Append"
Under Tools > Options > Media Management, the Overwrite Protection Level is set to "None"

I can see the tapes when mounted, and can Inventory them.
I can watch the job start and proceed as normal, till the error, then it just sits there and waits.....
Not sure what to do....they have run fine under this job and media set for over a year now.....Just can't figure out what went wrong...???

We have Server 2003 SP2, with exchange 2003 SP2
Backup Exec 10 rev. 5484
10 tapes (two week rotation of 5 tapes each - full backup every night)

Thxs
 
    Fubr

Answer : Backup Exec and Overwritable Media

DAT 72 will only give you 72 GB with 2.0 compression ratio or better, which is virtually impossible to achieve.  You are almost certainly running out of space on your tape.  The tape is 36 (uncompressed) GB / 72 (compressed) GB.