No, you can'tupdate from Blackhole 2.1.7, as they are different builds.
According to an earlier post, from you, when you wnet into the menu, Information, and About, your receiver stated that you had:
"experimental 2015-07-22"
That doesn't seem to be Blackhole 2.1.7, so are you sure you have blackhole 2.1.7 loaded on your receiver?
What happens when you hold down the Front Power Button, behind the front panel, after turning on the receiver, using the rocker switch, at the rear?
Does it recognize the USB stick, inserted into the front USB port, behing the pull down flap, near the power button?