Firmware Update Recovery

Use this guide if an automatic OnlyCat software update fails and you have been advised by Support to attempt a manual recovery.

Step 1: Enter USB MSC Mode on the device

Option A: Using the Setup Menu (recommended)

1. Press the setup button (circled) once to bring up the Setup Menu.
2. Press the setup button three times to move the selector down to USB MSC.
3. Press and hold the setup button to select USB MSC mode.

Option B: Hard Reboot (fallback)

• Press and hold the setup button for 15 seconds.
• The device will reboot and enter USB MSC mode automatically.

Step 2: Copy over the firmware update

1. Connect OnlyCat to a laptop or computer using a suitable USB Type-C cable.
2. OnlyCat should appear as an external storage device named "OnlyCat".
3. Drag the provided firmware file onto this storage device.
4. Wait a few seconds — OnlyCat should automatically start updating its software.

Tip: If OnlyCat doesn’t automatically eject after 60 seconds, you can manually eject it:

• On Windows: Right-click the OnlyCat drive in File Explorer and select Eject.
• On Mac: Click the Eject icon next to OnlyCat in Finder.

Step 3: If the update fails

• If the update process above does not complete successfully, please contact Support and provide the steps you’ve already tried.

Updated on: 27/01/2026