To reinstall the fan tray, use the following procedure:
Attach an electrostatic discharge (ESD) grounding strap to your bare
wrist and connect the strap to one of the ESD points on the chassis. For more information about ESD, see Preventing Electrostatic Discharge Damage.
Grasp the fan tray on each side and insert it straight
into the chassis. Note the correct orientation by the "this side up"
label on the top surface of the fan tray.
Tighten the captive screws on each side of the fan tray
faceplate to secure it in the chassis.