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As someone who works with multiple MIDI devices, including the Korg PadKontrol, Korg MicroKontrol, and the Edirol 61-key MIDI keyboard, I can say they are all excellent tools. However, getting them to work smoothly with Windows can sometimes be a challenge. Between driver installations, USB port quirks, and software configuration, the process can become frustrating enough that many users simply give up.
I ran into an issue that took hours of research to resolve. Windows recognized my MIDI controller in Device Manager, and the correct drivers were installed. But the device never appeared in Reason 4 under the MIDI controller list. Everything looked fine on the surface, yet nothing worked.
Eventually I discovered the cause. Windows assigns MIDI ports based on the USB port you use. Each time you plug the same controller into a different USB port, Windows treats it as a new device and creates a new MIDI assignment. Over time, I had filled all ten available MIDI port slots. Windows will not clear them automatically, and once that limit is reached, new devices stop showing up in your music software.
The fix is to clear out those unused MIDI entries in the registry so Windows can rebuild them.
How to Fix the MIDI Port Assignment Issue
Before making any changes, be sure you are comfortable working with the Windows Registry.
Step 1: Open the Registry Editor
- Click Start
- Click Run
- Type regedit and press Enter
Step 2: Navigate to the MIDI Port Section
Browse to the following location:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Drivers32
Step 3: Remove Duplicate and Unused MIDI Entries
Inside this folder, you will see entries labeled:
midimidi1throughmidi9wave1throughwave9
Delete the duplicate or unused entries that are taking up the available port slots.
Step 4: Restart and Reconnect
Restart your computer and then reconnect your MIDI controller. Windows will rebuild the necessary entries automatically.
Results
After clearing the registry and reconnecting my device, Windows recognized my Korg PadKontrol immediately, and Reason picked it up with no further issues. Without this cleanup step, I never would have identified the root cause.
Hopefully this guide saves you the time and frustration that I went through when troubleshooting the issue.