I have followed all instructions to set up Sync on my PC and then added my iPhone and iPad. There is no sync taking place in any direction, between any of the devices and I cannot understand why. All the Firfox Sync downloads are new and therefore I assume the latest version. All the devices are signed in to the same, correct account. Pressing the Syc icon does nothing except animate it. I have no idea what to try next. Ideas welcome please. Thanks.