I had the problem myself an was able to recreate the problem a couple times, can't post any links because I'm new on here. But this is the fix download the stock 4.2.2 zip cmw/twrp friendly one not the one containing the .tot file an extract the entire zip or use winrar to navigate to the boot image an extract it.
Flash the boot image, this will allow you to reaccess download mode and or recovery if you have one installed need anymore help pm me. Also on a side note I couldn't find a working adb driver for the g2 maybe it's just bad luck or lack or research but I was able to get adb fully working with two diff drivers.
1 the adb drivers for the HTC one don't ask me why an minimal abd and fastboot drivers worked as well.