Here you can download USB and ADB driver for your Lenovo S60 smartphone by Lenovo comes with Qualcomm cpu. This driver will also work for USB ADB and Q Usb for Flashing handset. Just download from below link and run it. Remember this driver for only PC Windows.
Download Lenovo S60 Q-USB USB ADB Drivers Official
Supported OS : Windows XP / Windows Vista / Windows 7 / Windows 8 / Windows 8.1 / Windows 10 both 32 and 64 bit