You can download PC Driver for Asus ZenFone 5 ZE620KL for windows from below link. These driver are needed to connect mobile phone with pc. These drivers are tested and working.
Download Asus ZenFone 5 ZE620KL Q-USB USB Drivers
Supported OS : Windows XP / Windows Vista / Windows 7 / Windows 8 / Windows 8.1 / Windows 10 both 32 and 64 bit