c:\adb>fastboot flash recovery openrecovery-twrp-2.7.1.0-pyramid.img
sending 'recovery' (8434 KB)...
OKAY [ 1.862s]
writing 'recovery'...
FAILED (remote: not allowed)
finished. total time: 2.178s
sending 'recovery' (8434 KB)...
OKAY [ 1.862s]
writing 'recovery'...
FAILED (remote: not allowed)
finished. total time: 2.178s