Are you having problems with stale cookies? I recently assisted a customer over email who was having trouble using his Disklavier Piano Radio. I discovered the solution to this issue initially on Kevin Busse’s website, who in turn learned the solution from Yamaha’s Noah Jolly. You can read more about Noah Jolly on his website, Ground Grown Circuits. The procedure, and the related caveats, follows.
Why Firmware Comes First
The original DKC-800 used an old security protocol when it phoned home to Yamaha. In October 2021, Yamaha disabled this entirely. Once Yamaha upgraded its servers, every control unit running pre‑update firmware lost the ability to finish the handshake with Yamaha.
See my article on updating E3 / DKC-800 / DKC-850 firmware, and make certain you’ve done this before trying anything else.
Make Sure You’re Connected!
Verify that you’re actually getting internet at the piano. An easy way to do this is to plug a computer into the Ethernet cable, wireless bridge, or other device you’re using to connect your piano. Make sure that the laptop can reach the internet using that same connection.
I’ll typically also do an Ookla speed test, and make sure I’m getting more than the minimum 3 Mbps the Disklavier requires.
If you need any guidance on connecting your piano to the internet, see my article on connecting Yamaha Disklaviers to Wi-Fi.
What Are Disklavier “Cookies”?
Yamaha stores your MusicSoft / Disklavier Radio inside the control unit. Think of it as a bookmark that says, “Hi, I’m this subscriber.”
When that file is:
Tied to the previous owner’s account
Stale after you changed your password or e‑mail
Corrupted by a power loss mid‑session
Maxed‑out after years of never being cleared
…the piano can’t authenticate even though the network test passes and firmware is current.
That’s when deleting cookies helps.
How to Delete Cookies on a DKC‑800 / E3
Press [SETUP] on the DKC‑800 remote.
Tap the ▶︎ Right Arrow until you reach the last page; the only item there is “Reset.”
Highlight Reset and press [ENTER] (center of the arrow pad).
The reset line initially shows “Reset = Parameter.” Press [+/Yes] or [−/No] until it reads “Reset = DeleteCookies.”
Press [ENTER] again. When asked to confirm, choose [+/Yes].
The control unit briefly processes and returns to the main screen—cookie deletion is complete.
Re‑enter your Yamaha ID and password at the login prompt to resume Disklavier Radio.
Need a Hand?
If you hit a dead end—feel free to contact me. I stock pre‑loaded USB drives with the latest firmware and can perform the update or cookie reset on‑site throughout Maine and New England.