How did you do that? Just removing the device doesn't delete the driver. It just un-links them Sometimes Windows gives you the extra option to do so but if it thinks it's still in use it doesn't. But if you have the CH340 driver installed, then plug in the CH340 and Windows will just link the driver for you. No need to dig through.inf files.
Software Description: USB to serial CH340 / CH341 for WINDOWS 32-bit / 64-bit driver support WINDOWS 98 / ME / 2000 / XP / Server 2003 / VISTA / Server 2008 / Win7 / Win8 / Win8.1 32 Bit / 64, through Microsoft's digital signature authentication, the computer terminal emulation standard COM?, Serial serial devices including serial port monitor.
But the fact you 'installed' FTDI drivers for it I start to think it's NOT a CH340 but just a Chinese/counterfeit FTDI which will install with the latest FTDI drivers but just will not work. Google 'FTDI gate'.