I don't have a Korg keyboard so can't try it myself.
However if it's the same one you have, it looks like Korg have found the problem and issued a new driver.
If it was me though, if I hadn't done so already, I'd definitely take a backup image of the system drive/whole computer in its working state before trying the upgrade again.
Originally it was a month, but somewhere along the way, Microsoft changed it so now you only have 10 days to rollback.
Also, I did once have an experience where the rollback didn't work.
Maybe it's more reliable now but it still don't entirely trust it.
Ah I'm sorry that didn't work... was hoping it would be an easy fix. :(
I did see some workarounds which people mentioned before the driver update was published but they did seem to involve changing the registry so not risk-free.
I'd have tried disconnecting the keyboard, uninstalling the driver (seem to remember there is some option to fully remove the driver software from system), then running the W10 update and installing the new driver from there, maybe even before re-connecting the keyboard. But I'm not sure that's sufficiently different from what you already tried that it would change the result.
Hi all, I posted here to inform some people who have problem with the korg usb midi driver since the 1903 May win 10's update. For the facts, there is a big bug with Korg usb midi driver when you update from version 1809 to version 1903 of win 10. The result is for an unknown reason all KORG...
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