When an older LabPro is first used with Logger Pro 3, Logger Pro will update the internal operating system software (OS) in the LabPro. That update can take a long time, up to 30 minutes if a serial cable is used. Sometimes the update fails because the LabPro batteries are low, the cable is loose or is disconnected, or the user stops the update part way.
When the OS update fails, try restarting Logger Pro and let it attempt the update again. Sometimes the failure will disable the USB port, so try the serial port connection if possible. If that fails, there are two options.
1) Send the unit back to us, and we will take care of it. Give us a call for more information.
2) Update the LabPro using a TI Graph Link cable. (Usually a LabPro that can be updated this way will give a beep-beep, beep-beep sound when you apply power, flashing all three lights on each beep.) If you have a Graph Link cable, download the appropriate updater from the Vernier Web site.
https://www.vernier.com/support/updates/labpro-and-cbl2/
Follow instructions there to complete the update.