When you first attach a projector to a computer the OS will load a generic profile with the driver. The projector will be uncalibrated otherwise. Just like any other display it will need to be calibrated.
I teach at multiple campuses around town and have to use various display options in the classrooms. The projectors have always been a nightmare for me to deal with because calibration is an unknown concept in the IT departments of these campuses so the projectors are never calibrated for use with the campus computers. My ultimate solution is to carry a laptop with me and in some cases a screwdriver. I plug the projector into my laptop (sometimes I need the screwdriver) and then I calibrate the projector from my laptop. I save the calibration ICC profile as the campus name and room number. Then when I arrive in that classroom I setup my laptop and load that projector profile. When they change the lamp, or once a semester, I re-calibrate.
Joe