Please read the readme notes before using and installing the download. To download the file, click on the download link / filename in the last column.

Download for M4U eX

Description Operating System Version Size Date Readme Download
universal MIDI Port driver Windows 10 32-bit
Windows 10 64-bit
Windows 11 32-bit
Windows 11 64-bit
1.5 1.468 KB 2023-01-17 readme.pdf

ESI MIDI Port driver

The ESI MIDI Port driver (v1.5 or higher) supports the following products:

- M4U, M4U XL, M4U XT, M4U eX
- M8U, M8U XL, M8U eX
- RoMI/O II (Rev. B)
- KeyControl 25, KeyControl 25 XL, KeyControl 25 XT
- KeyControl 49+, KeyControl 49 XT
- KeyControl 61 XT
- Xjam
- Xkey 25, Xkey 25 Air
- Xkey 37, Xkey 37 Air

Please note that this optional driver works only with 32-bit and 64-bit versions of Windows 10 and Windows 11. Older versions of Windows are not supported.

After the installation of the driver, the products listed above will not use the generic driver that is included with Windows, but the ESI MIDI Port driver. This makes it more convenient to use multiple decides at the same time and all the devices are accessable via the multiclient support in multiple applications at the same time.


Make sure that you have downloaded and unzipped the driver file. To start the installation, launch the setup program, which is an .exe file that is inside the driver download, by double clicking on it. Typically the filename is something like ESIMidiport_vX.YY_setup.exe where X.YY is the version number of the driver. When launching the installer, Windows might display a security message. Make sure to allow the installation. After that, the following dialog will appear:

Click Next and then the following dialog will appear:

Now click Install. Files are now being copied:

After a while the installation then will be completed and the following dialog will appear:

Please restart your computer by selecting Yes, restart the computer now and then click Finish. After the reboot, you can connect and start using your MIDI device with the ESI MIDI Port driver. If you use multiple devices, they will all be usable at the same time.


In case you need to uninstall the driver at a later time, you will find it under the list of installed Apps in the Windows Settings dialog. You can simply remove it there. Even after the driver has been removed, you can use your ESI MIDI devices via the generic driver that is included within Windows.