Thankgod xda developers exist : http://forum.xda-developers.com/verizon-lg-g3/help/unable-to-access-adb-t2830087
Just had to delete adbkey file in C:Users/$Name/.android adbkey.pub was missing.
Restart after this and both files are there.
If this does not work : - Try Revoke USB DEBUGGING Authorization. - Enable USB debugging again.