HP Officejet 7500A Wide Format e-All-in-One Printer - E910a - Manual (Page 81)

5. Twist the orange cap to snap it off.
NOTE: Make sure the plastic tab is entirely removed and that the label is slightly
torn, revealing the vent channel.
6. Using the colored shaped icons for help, slide the ink cartridge into the empty slot
until it clicks into place and is seated firmly in the slot.
CAUTION: Do not lift the latch handle on the print carriage to install the ink
cartridges. Doing so can result in incorrectly seated ink cartridges and printing
problems. The latch must remain down in order to correctly install the ink
cartridges.
Replace the ink cartridges 77