Iphone xs won't sync past step 3 on windows 10 desktop

Been syncing step 3 slowly recently but has now stopped totally. Syncing iphone xs with itunes on desktop and sync reaches step 3 of 5 'preparing to sync' and just sits there forever (with wheel spinning). Any attempt to get out freezes the pc screen and my only exit is ctrl/alt/delete . I've tried sync via cable and wi-fi, rebooted both units,changed a few settings ref internet searches,uninstalled and re-installed itunes on pc and music app on iphone and even restored the iphone but sync still stops when reaching step 3 of 5. Any other ideas please ? Thanks