I have recently bricked my Kindle Fire HD 7". Upon pressing the power button, the kindle fire boot logo will flash, but the device will not boot. I have a fastboot cable, and I think the proper drivers are installed as it shows up as an Android USB Composite Interface under "Kindle Fire" in Device manager. But, upon plugging the kindle in with a factory cable, allowing it to enter fastboot, navigating to platform-tools and running adb-devices, the device is not found. I then perform adb kill-server, the adb devices, but still not found. I need it to be found in order to issue fastboot commands and restore it. How do I go about this?