My company's backup server is an HP Proliant DL 380 G3 and I installed an HP 64-bit/133MHz Dual Channel Ultra320 SCSI host bus adapter to it. I also purchased as my backup devices 2 HP StorageWorks SDLT 320 drives. They are both connected 1 on each channel to the card. My OS is Windows 2003 Server and I use BrightStor Arcserve 11.1 to do the backups. My problem is that the backup process starts fine and goes for about 10 minutes and then produces the error 6304 'unexpected scsi sense code'. This is very frustrating especially the equipment is practically brand new. I feel like it is not a hardware issue and some configuration is causing these errors. I also see error 6300 'Windows NT SCSI port error'. It happens on both drives and I haven't had backups in weeks!!! Please Help.