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As someone who works with several MIDI devices—including the Korg PadKontrol, Korg MicroKontrol, and Edirol 61-key MIDI keyboard—I can say they’re all fantastic tools. But getting them to work properly with Windows can be challenging. Between driver installations and software setup, the process can be frustrating enough to make some users give up altogether.
I ran into a problem that took me hours of searching to solve: Windows simply wouldn’t recognize my device. It appeared in Device Manager, and the drivers installed correctly, but it never showed up in Reason 4 under the MIDI controller list. This was baffling—until I discovered the root cause.
The issue comes from how Windows assigns MIDI ports. Every time you plug a device into a new USB port, Windows treats it as a new device and installs a fresh set of drivers. Over time, I unknowingly used up all 10 available MIDI port assignments. Once that limit is reached, Windows doesn’t automatically clear old assignments, and new devices stop working correctly.
The fix is to clear out those excess registry entries and free up the MIDI slots. Here’s how:
- Open the Registry Editor (Start > Run > type
regedit). - Navigate to:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Drivers32 - Delete the duplicate MIDI entries (midi1 through midi9) and any unused wave entries (wave1 through wave9).
- Restart your system and reconnect your device.
After following these steps, Windows recognized my Korg PadKontrol immediately, and everything worked perfectly. Without this registry fix, I never would have figured it out. Hopefully, this guide saves you the time and frustration I went through.