Asha 500, 501, 502 and 503 does not support PC Suite. These phones support only three modes in USB, i.e., Charging, Modem and Mass Storage. Other than that, the phones does not support any other function via USB.
Nokia PC Sute is compatible with older Symbian and S40 phones only. The Asha phones before 500 are compatible but not the 500, 501, 502 and 503. These phones run on new Nokia Asha 1.0 platform(currently version 1.1.1) which is the next generation of S40 and Nokia PC suite is not compatible with this new platform.