Hi,
I have used a CH340 Nano Clone before with the drivers installed and it worked fine.
Now it will not program, I checked in device manager and under 'ports' the CH340 label is gone.
I tried re-installing the drivers however there was no change.
I have spent ages trying to figure this out and have finally decided to ask for help, what do I do?
Thanks,
Does a new port appear in the ports section of Device Manager after you plug in your Nano?
Nope.
All there is is "Communuications Port (COM1)
Which has always been there
Does any new entry appear anywhere in Device Manager after you plug it in?
Try a different USB cable. You may have a bad cable. There are also charging cables that don't connect the data lines. These will light up the power LED on your Nano but it's never seen by Device Manager.
Nothing else appears.
I have also tried different cables (one of which I used last time to program so I know it worked)
Does anything appear under HIDDEN devices or UNKNOWN devices that could relate to your nano ?
Also it may be worth re-install the CH340 / 341 drivers.
Turned on hidden devices, still shows nothing 
I have also tried re-installing the drivers many times
Can you link us to where you got your drivers ?
Did you install them as Administrator ? (real administrator not the sudo one)
Is there a possibility for you to try with another computer ?
What operating system BTW as that could have bearing.
If its windows 10 there was a recent update that crashed a lot of USB devices especially web cams.
Ok -
I finally found out the problem (for one of the nanos atleast), it had nothing to do with the IDE or drivers. A component on the underside fell off 
(see image)
That could be fixed fairly easily with a standard soldering iron, you can buy those capacitors for super cheap if the one that fell off is lost. Of course, with how cheap those clone nanos are it might not be worth the effort but sometimes it's fun to fix something instead of throwing it away. That's one of my favorite things about learning DIY electronics, moving away from that throwaway consumer mentality.