Difficulty playing the high E note for flute?

I find it hard to play the 2nd octave E note for the flute... I have no problems when it comes to playing the 2nd octave C, D, D#, F, G etc but find it difficult for the E note... I have practiced and I can get it at times, but its the only note that I tend to get out of tune. Im fine with the other notes from middle C to high A... any tips to perfect this E note?