Mac OS X 10.3.3: USB device, FireWire device, RAID card or SCSI card doesn‘t work after updating to 10.3.3

Symptoms you might see on an affected system include:

• External or internal SCSI devices that are not recognized.
  
• USB or FireWire disks (or devices with file systems) do not mount.
  
• If the startup volume is on a SCSI drive, the computer may stop responding ("hang") during startup.
  
• Apple System Profiler may recognize some devices that are not recognized elsewhere in the system.

If the affected computer can start up, update to Mac OS X or Mac OS X Server 10.3.4.

If the the computer won't start up, try using Safe Mode to update to 10.3.4. If it still won't start, these are some tips you can follow.