On page 42 of the owners manual it states that Error 3 is caused when the boot ROM checksum does not match.
This is very rare and very odd.
But it looks like you need to carry out the boot ROM software upgrade/reflash process.
See here hawk800 / Discussion / HAWK Software:How to upgrade boot software on HAWK boards V1.5 and up
If your Poly still works, backup your patches first.
/Mike
On Tuesday, October 7, 2014 9:59 AM, "ultragalore@... [korgpolyex]" <korgpolyex@yahoogroups.com> wrote:
Not sure why this is happening. The manual says I'm dumping the wrong filetype in the hawk, but it happens on boot, I'm not sending any messages to it.
When I started the h800 for the first time I burned the firmware and when that was done (sucessfully) I might have sent sysex to the system while in flash mode though..