Fastboot doesn't recognize OnePlus3 although adb does When trying to root my OnePlus3 I ran into the issue that when running fastboot devices my output is blank. Some people said that even while it returns a blank output other commands should still work but fastboot oem unlock just says it's waiting for my device without ever proceeding. Also in my device manager I can see ´Kedacom USB device > Android Bootloader Interface´ and I think that might be the problem which I also found in "Kedacom USB Device doesnt work with fastboot Nexus 5x". However no solution is provided here.

When I'm using adb devices after a normal boot it returns List of devices attached 2a04cf0c        device and in my device manager I can also see USB devices &gt; ADB interface
I had the same problem with a OnePlus One. The problem is that Windows 10 does not let you install the right driver, assuming you are using Windows 10.

I was able to solve it by using a Windows 7 machine instead.

Another solution I found, but haven't tried, is to disable driver verification. 
This should allow you to install the right drivers, even if the verification fails. However, I do not recommend this as it makes your computer vulnerable to bogus drivers.