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Device Not Found? (App Note)

If your LabJack device is not found, try the following steps.

USB is the simplest connection type, so try to get that working first.

If USB is not working

Close other related software

LabJack devices can only be connected via USB by one program at a time. Try closing all other programs that might be talking to the device, then try again.

Check for installation success

Windows: Open Windows Device Manager (WDM). Disconnect & reconnect the USB cable and watch WDM for an entry that disappears and appears.  If you see error code 28 ("Drivers for this device are not installed") or other problem, follow instructions to make sure the device drivers are installed correctly.

Linux: Execute the command lsusb. If a LabJack device does not show up, log out and log back in again. If that doesn't cause the device to appear in lsusb's output, re-run the installation.

macOS: Run the following command in the Terminal: 
system_profiler SPUSBDataType | grep LabJack
If no output shows, please contact us.

Check for USB communication failure

Try the steps described here: USB communication failure.  If USB is not enumerating at all look at section F.

Check you're opening the right software (and only one!)

Close all software and only run 1 program.  It is sometimes possible to use multiple programs, but it complicates troubleshooting.

If you have a T-Series LabJack device such as the T4 or T7:

  • Use LJLogM or LJStreamM. There are similar programs called LJLogUD and LJStreamUD, which don't work with T-series devices.

  • Use Kipling for configuration and firmware updating.

If you have the LabJack U3, U6, or UE9:

  • Use LJLogUD or LJStreamUD. There are similar programs called LJLogM and LJStreamM, which don't work with the U3, U6, or UE9.

  • Use LJControlPanel for configuration.

  • Use LJSelfUpgrade for firmware upgrading.

See also: what software to use for which device.

If Kipling or LJControlPanel is working, but LJLog/Stream is not

LJLog/Stream (e.g. LJLogUD or LJStreamUD) use configuration files to determine what device to open. These configuration files end in _open.cfg (e.g. LJLogUD_open.cfg).

The default _open.cfg files try to open all devices. To get the default _open.cfg files:

  • Close LJLog/Stream.

  • Delete the current _open.cfg file—it's located in the LJLog/Stream working directory.

  • Re-open LJLog/Stream—this will create the default _open.cfg file in the LJLog/Stream working directory.

Besides newer versions of LJLogM (1.09+), these applications just try to open a device one time when they first start.  If that does not work you need to close the application and re-run.  With LJLogM 1.09+, if you see an error message related to device opening go to the Configure Open Device tab.

If a network connection is not working

WiFi: Use the USB connection in Kipling to watch the status of the WiFi connection.  See the troubleshooting tips towards the end of the Setup WiFi and Ethernet App Note.  If the WiFi connection is not joining (not associated), see the tips labeled "not associated".  If the WiFi connection is associated but there is some problem after that, see the other tips, and also look at general networking tips (see the Ethernet section that follows here).

Ethernet: See Ethernet Troubleshooting towards the end of the Basic Networking App Note.  Start with items 1 & 2.

Moving on

Once USB communication works, you should try the quickstart for your device.

Contact us

If you still can't get the USB connection to work, please contact us.

We'll probably need to know the following:

  • Your operating system version

  • Which LabJack device(s) aren't working

  • What software isn't working

  • Which connection types aren't working:

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