External SCSI disks: how to remove them correctly

I'm running Windows 2003 Server Enterprise. My computer has three internal
hard drives, and an external Micronet Datadock chassis populated with five
SCSI drives. I periodically copy data to one of the external hard drives,
then before I leave work for the day I push a button on the Datadock that
unlocks the drive from the chassis, then I remove it and take it home with
me. In checking the Server log, I found that I have many error messages
stating that a drive was removed without being properly prepared. It also
says that I should have clicked on the Safely Remove Hardware icon in the
system tray. But, I have no such icon. In Computer Management, these drives
do not appear under Removeables. Query: what is the correct method of
removing one of the external drives, so that I avoid operational problems
and error messages?