Post Calibration Colour Cast
Calibrator Is Not Functioning Correctly
This is unlikely if your calibrator is brand new, but could very well be the case if your calibrator is older. If it was previously working properly with the same screen, it will almost always be a failure in the calibrator. The average lifespan with older calibrators such as the Spyder3, Eye One Display 2 etc, is realistically 2-3 years. After this time, they begin to drift far enough out of spec. and can become problematic. The Calibrite ColorChecker Display Pro (formally X-Rite i1 Display Pro, has since been rebranded to Calibrite) has a sealed filter design, and is designed to last significantly longer. Read more on Monitor Calibrator Longetivity below.
Calibrator Is Reading the Screen Incorrectly
If you have a newer LCD with LED backlighting or a very wide gamut monitor, your calibrator may not be reading your screen correctly. Your only option is to upgrade your calibrator to a newer model designed with these technologies in mind, like the Spyder4 or ColorChecker Display Pro. Older calibrators were designed before these screens even existed and simply can't read them properly.
Native White Point is Lower than the White Point Selected
Lower end screens can be very temperamental with white point adjustments. Try re-calibrating to the native whitepoint, which is usually available in your calibrator's settings, and see if this provides a better result. Be aware that the whitepoint will then be whatever the screen naturally displays, and therefore not necessarily that useful.
Here's some info from X-Rite on this:
Color casts on laptop/LCD displays can be the result of the white point selected. Very often the native white point on these displays is lower than the white point selected. When this is the case, the software based calibration uses curves to raise the color temperature. Driving the monitor to the higher color temperature can lead to a magenta cast.
Example: If the native white point on your monitor is 6200K, but 6500K is selected as the desired white point, a magenta cast could be the result.
The proper strategy here is to select "monitor native" as the white point.
