If it was permissible to celebrate a Birthday, we should have been commanded to celebrate the Birthday of Nabi (S.A.W), the Ambiyaa (A.S), the Sahabah (R.A) and the Saints. None of this is commanded. This 'celebration' is a clear imitation of the Kuffaar. It is Haraam. Moreover, many more Haraam activities take place at such events such as: playing of music, photography, intermingling of the sexes, extravagance, wastage of time, wastage of money, and wastage of energy. Practicing it further obligates a futile activity. Desist immediately.