[Q] need help unbricking nexus 7 topic

okay, so i tried to return my rooted nexus 7 to stock using wugfresh toolkit. for some reson it failed when flashing to stock and locked the bootloader. now whenever i try to unlock the bootloader to flash stock manually i get this...

chris@Chris:~$ fastboot oem unlock
...
(bootloader) Unlocking bootloader...
(bootloader) erasing userdata...
FAILED (status read failed (No such device))
finished. total time: 31.426s
chris@Chris:~$ fastboot oem unlock
...
(bootloader) Unlocking bootloader...
(bootloader) erasing userdata...
FAILED (status read failed (No such device))
finished. total time: 121.599s
chris@Chris:~$ fastboot oem unlock

Anyone have any suggestions? i have tried multiple usb cables and multiple computers. also it is not recognized by windows but fastboot is recognized in linux.