My printer says install magenta what does that mean

It means for you to install the magenta ink. Magenta is a color. You have 4 colors. Yellow, magenta, cyan, black

You can download the user manual at
www.brother-usa.com/.../Users%20Manual/UM_MFC_240C_EN_249.PDF

a Open the ink cartridge cover.
If one or more ink cartridges are empty,
for example Black, the LCD shows
Ink Empty Black and
Replace Ink.
b Pull the lock release lever down and
take out the ink cartridge for the color
shown on the LCD.
c Open the new ink cartridge bag for the
color shown on the LCD, and then take
out the ink cartridge.
d Remove the protective yellow cap (1).
Improper Setup
DO NOT touch the area shown in the
illustration below.
Note
If the protective yellow caps come off
when you open the bag, the cartridge will
not be damaged.
e Each color has its own correct position.
Insert the ink cartridge in the direction of
the arrow on the label.
f Lift each lock release lever and push it
until it clicks, and then close the ink
cartridge cover.
g If you replaced an ink cartridge, the LCD
may ask you to verify that it was a brand
new one. (For example,
Did You Change Blck?) For each
new cartridge you installed, press 1
(Yes) to automatically reset the ink dot
counter for that color. If the ink cartridge
you installed is not a brand new one, be
sure to press 2 (No).
If you wait until the LCD shows
Near Empty and Ink Empty, the
machine will automatically reset the ink
dot counter.
Note
If the LCD shows Install after you
install the ink cartridges, check that the ink
cartridges are installed properly.

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