There are a few possible causes for a USB drive to not be recognized by LabQuest:

  1. If the USB flash drive doesn’t appear to work, cancel the Save or Open, and try again. You need to allow about 10 seconds for the drive to initialize after it is connected to LabQuest.
  2. Rebooting the LabQuest may help.
    • Original LabQuest: Tap Home, choose Control Panel, then tap Reboot.
    • LabQuest 2: Tap Home, choose System, and then Reboot.
    • LabQuest 3: Tap Settings and then Reboot.
  3. If you have multiple LabQuests, test the USB drive on a different LabQuest. The problem might be with the drive, or with the LabQuest’s USB port.
  4. Make sure that no automatic update files (files with an LQA or SWU extension) are on the drive unless you are using the file to update that unit. In particular, a drive with a LabQuest 2 update on it will result in the original LabQuest not seeing the drive at all (it actually purposefully ignores it.) Likewise, multiple LQA or SWU files on the drive may result in unexpected behavior.
  5. There may be a physical incompatibility between the drive and the LabQuest preventing a connection. Physically short USB flash drives may not work. The USB “A” connector (the silver part) must be at least 12 mm in length from the base to the tip. There are some USB drives that have short connectors, and so have problems connecting to many computers and other devices. Additionally, some USB drive cases are too wide, preventing the connector from complete insertion by the casing of the LabQuest unit.
  6. The drive may have a capacity that is too high. More recent versions of LabQuest App can read drives up to 64 GB, but if you are are updating from an older version (pre-1.5) of the original LabQuest, the drive has to be 4 GB or smaller.
  7. The drive may be in a format that LabQuest cannot read. LabQuest supports the following formats: FAT and FAT32. Note that this list does not include Mac OS Extended, the usual macOS format, and it does not include exFAT, which is Microsoft’s format especially for USB flash drives. Note that Windows will not format a 64 GB drive to FAT/FAT32 without third party tools, so if you are buying a drive specifically for the LabQuest we’d recommend you stick to 32 GB or smaller. To check and repair the formatting of the drive, follow these steps:

Windows
a. Right-click the drive icon and choose Properties.
b. Verify that the “File System” is listed as “FAT” or “FAT32” (but not exFAT).
c. Click the tools tab and select “check now”.
d. Check both boxes, “Automatically fix file system errors” and “Scan and attempt recovery of bad sectors”.
e. Click Start.

Mac OS X
a. Go to the folder: Applications/Utilities and launch Disk Utility.
b. Select the USB drive in the left column (with a white icon).
c. Choose the Erase tab and ensure that the format is “MS-DOS (FAT)”.
d. If the format is not “MS-DOS (FAT),” you will need to choose the Erase option. This will reformat the drive in the MS-DOS (FAT) format, erasing any existing data on the drive.
e. If the format is already MS-DOS (FAT), go to the First Aid tab and select Repair Disk.

See also:
My original LabQuest does not connect to computer or see a USB thumb drive.
Original LabQuest does not see the update file on USB drive.
LabQuest App Sensor Setup doesn't list any channels