IBM P09N4108 - Manual (Page 10)

The device driver is now uninstalled. Your computer will not recognize the CD-ROM
drive when it is connected to the computer unless you reinstall the device driver.
Disconnecting and reconnecting the CD-ROM
drive
Hot plugging is supported on the connection between the USB cable and your
computer. This means that the CD-ROM drive USB cable can be disconnected from
and reconnected to your computer whether the computer is on or off.
Attention
The connection between the USB cable and the CD-ROM drive itself does not
support hot plugging. If you disconnect the USB cable from the CD-ROM drive
while the USB cable is attached to your computer, it might cause damage to the
CD-ROM drive.
To avoid damaging the CD-ROM drive, turn off the CD-ROM drive before
disconnecting the USB cable from your computer. To disconnect the CD-ROM drive
from the computer, unplug the USB cable from the computer. To reconnect the
CD-ROM drive, reconnect the USB cable to the computer.
Attention
Do not disconnect and reconnect the USB cable in rapid succession or the
CD-ROM drive might not load properly. After disconnecting the USB cable, wait
at least 10 to 20 seconds, or until the hourglass icon stops displaying, before
reconnecting the USB cable.
1-6 USB Portable CD-ROM Drive