HP LaserJet 9040.9050 Multifunction Printer series - Manual (Page 222)

218 Appendix C MFP memory and expansion ENWW
5 Press the compact flash straight into the slot.
CAUTION Do not insert the flash memory card at an angle.
Note The first flash memory slot marked “Firmware Slot” is reserved for firmware only. Slots 2 and 3
should be used for all other solutions.
6 Slide the formatter board back into the MFP and tighten the two screws.
7 Plug in the power cord and connect all cables. Turn the MFP on.