This section aims to help the user solve and avoid problems while using the software and operating the instrument.

Common Problems

In order to benefit from these, the user needs access to a large number of settings in the API or the LabOne User Interface. The complexity of the settings might overwhelm a first-time user, and even expert users can get surprised by certain combinations of settings. To avoid problems, it’s good to use the possibility to save and load settings in the Config Tab. This allows one to keep an overview by operating the instrument based on known configurations. This section provides an easy-to-follow checklist to solve the most common mishaps.

Table 1. Common Problems
Problem Check item

The software cannot be installed or uninstalled

Please verify you have administrator/root rights.

The software cannot be updated

Please use the Modify option in Windows Apps & Features functionality. In the software installer select Repair, then uninstall the old software version, and install the new version.

The Instrument does not turn on

Please verify the power supply connection and inspect the fuse. The fuse holder is integrated in the power connector on the back panel of the instrument.

The Instrument performs close to specification, but higher performance is expected

After 2 years since the last calibration, a few analog parameters are subject to drift. This may cause inaccurate measurements. Zurich Instruments recommends re-calibration of the Instrument every 2 years.

The Instrument measurements are unpredictable

Please check the Status Tab to see if there is any active warning (red flag), or if one has occurred in the past (yellow flag).

The Instrument does not generate any output signal

Verify that the On/Off switch of the output at the correct readout channel has been activated in the In/Out tab.

The Instrument does not measure any signal

Verify that the On/Off switch of the input at the correct readout channel has been activated in the In/Out tab.

The sample stream from the Instrument to the host computer is not continuous

Check the communication (COM) flags in the status bar. The three flags indicate occasional sample loss, packet loss, or stall. Sample loss occurs when a sampling rate is set too high (the instrument sends more samples than the interface and the host computer can absorb). The packet loss indicates an important failure of the communications to the host computer and compromises the behavior of the instrument. Both problems are prevented by reducing the sample rate settings. The stall flag indicates that a setting was actively changed by the system to prevent UI crash.

The LabOne User Interface does not start (when running the LabOne on a PC)

Verify that the LabOne Data Server (ziDataServer.exe) and the LabOne Web Server (ziWebServer.exe) are running via the Windows Task Manager. The Data Server should be started automatically by ziService.exe and the Web Server should be started upon clicking "Zurich Instruments LabOne" in the Windows Start Menu.

If both are running, but clicking the Start Menu does not open a new User Interface session in a new tab of your default browser then try to create a new session manually by entering in the address bar of your browser.

The user interface does not start or starts but remains idle

Verify that the ziServer has been started and is running on your host computer.

The user interface is slow and the web browser process consumes a lot of CPU power

Make sure that the hardware acceleration is enabled for the web browser that is used for LabOne. For the Windows operating system, the hardware acceleration can be enabled in Control Panel → Display → Screen Resolution. Go to Advanced Settings and then Trouble Shoot. In case you use a NVIDIA graphics card, you have to use the NVIDIA control panel. Go to Manage 3D Settings, then Program Settings and select the program that you want to customize.

Location of the Log Files

The most recent log files of the LabOne Web and Data Server programs are most easily accessed by clicking on btn uielements session dialog um in the Config tab of the user interface. The location of the Web and Data Server log files on disk are given in the sections below.


The Web and Data Server log files on Windows can be found in the following directories.

  • LabOne Data Server (ziDataServer.exe):

    C:\Windows\ServiceProfiles\LocalService\AppData\Local\Temp\Zurich Instruments\LabOne\ziDataServerLog
  • LabOne Web Server (ziWebServer.exe):

    C:\Users\[USER]\AppData\Local\Temp\Zurich Instruments\LabOne\ziWebServerLog

The C:\Users\[USER]\AppData folder is hidden by default under Windows. A quick way of accessing it is to enter %AppData%\.. in the address bar of the Windows File Explorer.

windows explorer app data
Figure 1. Using the %AppData%\.. shortcut in Windows Explorer to access the hidden folder.

Linux and macOS

The Web and Data Server log files on Linux or macOS can be found in the following directories.

  • LabOne Data Server (ziDataServer):

  • LabOne Web Server (ziWebServer.exe):