800GB tapes showing as 391GB and 400GB tapes also showing as 391GB

[bbrownfield]

We're currently using a HP 4048 2 Ultr 920 Drive Tape Library with 400GB capacity tapes. The tape library has two Ultrium 3- SCSI tape drives. I've recently added several 800GB tapes to the library and I noticed that on our monthly backup, it was still spanning 4 tapes. I checked Backup Exec and found that it was showing all the 800GB tapes as the same size as the rest of the tapes which are 400GB. I've researched here and on the net and found lots of discussion about compression but the compression ratio is identical on both types of tapes during the backup jobs.

Basically, I'm getting the same capacity from the 400GB tapes that are getting the same compression as the 800GB tapes which tells me that it's not seeing the tapes as 800GB.

[Anup]

what driver you are using for tape drives?

Use symantec tape drivers.

[bbrownfield]

I'm using the Symantec drivers...version 5.1.25

[Ken_Putnam]

If you go to the media tab and do a right click\Properties on one of the larger tapes, what type of media does BackupExec think it is?

I seem to recall problems with LTO-3 tapes when v11 first came out.  IIRC, the solution was to "initialize" the tapes using the mfg utility before using in BackupExec