The German Railway in H0


64-bit drivers for Lenz LI-USB on Windows 7

NOTE: These drivers will only Work with the LI-USB unit from Lenz. This is not the same as the Ethernet unit. If you have the Ethernet unit, you will have to get matching drivers from Lenz.

IMPORTANT: As of April 2016, I no longer support these drivers. They will work with Windows 10 32-bit and 64-bit, but you might have challenges installing them as they are not signed. Check the comments section for other people's advise and tips. To connect your Lenz system to your PC, I recommend using the Lenz Ethernet Interface instead. If you are in the market for a new digital system, I highly recommend checking out the Märklin Central Station that fully supports DCC, and can do loads of automation without the need for a PC.


UPDATE: The drivers cannot install on 64-bit versions of Windows 8 without some additional work. Please checkout my article on Lenz LI-USB and Windows 8.

Lenz Elektronik GmbH has not released any 64-bit drivers for their LI-USB interface. This means that if you own a computer with a 64-bit platform and a 64-bit operating system, you are unable to use your LI-USB hardware.

Luckily enough, Lenz has based their LI-USB system on the FT232BL chip which is a well known piece of hardware. Unfortunately, it is not enough to just download and use the reference drivers. The driver information files need some modification in order to work, the same modification, that Lenz has not yet fixed, thus leaving their 64-bit platform customers without the ability to use their LI-USB (which is a rather expensive investment). Lenz, that is not very nice.

Now, I have spent the 1 hour of work, including testing, needed to fix this problem!

I have not made any changes to the driver files themselves, I have only added the Lenz Vendor Id and Product Id to the driver information files. These drivers are genuine FTDI Chip drivers, available for free, from http://www.ftdichip.com/

Here you go:

Download the drivers: Bahnfan.net_FTDI_CDM_2.06.02_12_01_2014.revised.zip (1.15 mb)

32-bit and 64-bit LI-USB drivers for Windows 7, download them, install them, enjoy!

Supported Operating Systems

The reference driver software can be used with the operating systems listed below. Notice this includes the 32-bit versions as well, meaning that you can update your Lenz drivers (which has not been updated since 2006) and correct several bug fixes.

Windows Server 2008 R2
Windows 7
Windows 7 x64
Windows Server 2008
Windows Server 2008 x64
Windows Vista
Windows Vista x64
Windows XP
Windows XP x64
Windows 2000
Windows Server 2003
Windows Server 2003 x64

Installation Guide

To install the drivers unzip the packaged and place it somewhere on your harddisk.

1. Open the Windows start menu, right click "Computer" and choose the menu item "Properties"

2. From the side panel choose the link "Device Manager"

3. Now right click the node "LI-USB" and select the menu item "Update Driver Software".

4. In the window that opens choose the option "Browse my computer for driver software".

5. Browse to the folder where the driver files are located:

6. Windows will warn you about unsigned drivers. Choose the option "Install this driver software anyway".

7. That's it! The driver software is now installed and you can start to use your Lenz LI-USB with 64-bit Windows 7. Enjoy it!

Known Problems


The Lenz software complains about being unable to find the LI-USB interface and JMRI claims that your port is "in use".


This problem seems to be happening when you have been trying to use both JMRI and the Lenz Software from within the same Windows session, but not at the same time (which of course will not work at all since they will fight for the COM port).

I have not yet determined which application is initiating the problem, but it looks like the COM port is not released thus preventing any further use. The problem will prevent LI-USB from working correctly for the remainder of your Windows session. If you only use JMRI the problem does not seem to occur, likewise if you only use the Lenz software the problem does not seem to occur either. I have tested this on Windows 7 Professional 64-bit.


A restart of your computer will release all locks on the port and the problem will go away. However, the problem will return in your next Windows session if you keep using more than one type of control software. I can only recommend that you only one type of control software.

Uninstalling the driver software

When you uninstall the reference driver software, please remember to check the check box "Delete the driver software for this device" in the uninstall window.

Contact information

You can alway contact me if you have any questions. I really need more people to test this thing, so we can identify the problems that people might experience getting this thing to work. Thanks in advance! :-)

Happy modelling!

UPDATE 04/21/2014: Updated drivers with support for additional hardware configurations. If you have had any problems with recognizing the LI-USB hardware, they might be fixed now.