Replacing the SD card

You may need to replace or rewrite the microSD card that comes with your Hotspot if it:
  • shows "Disk Error" in the diagnostics
  • is not booting up (cannot connect over Bluetooth anymore after pressing the pairing button)
  • shows a solid or flashing green status LED
  • shows a very old block height and/or firmware version in diagnostics 
  • power cycling has resulted in unknown micro SD card errors, such as corrupted files. 
  • If it's stuck in the same block after 2 diagnostics were done 24 hours apart
The card is considered a consumable, wearing, user-replaceable part.
THIS PROCEDURE SHOULD ONLY BE USED FOR MNTD. and RAK v1.5 or v2 hotspots (shipped in 2021 onwards). RAK v1 hotspots (units shipped in 2020) will have their identity stored on the SD card which must be restored from your backup. 

Steps to take:

1. Download the Firmware file (works best if kept as a ZIP) (updated to version 2023.04.18.0):
Firmware Download

2. Install the balenaEtcher flashing tool you can find Windows, Mac and Linux versions
(optional) a new replacement microSD card. We now recommend a SanDisk or Samsung 64GB High Endurance card.
3. Follow the card replacement procedure:
    1. Power off the hotspot (unplug from power)
    2. Carefully peel off the tape protecting the microSD card slot, it is below the gold/black sticker on the side of the hotspot where the antenna is, next to the status LEDs.
    3. Remove the microSD card inside, there is a small lip on the bottom part which you can use to pull it out, some people prefer to use tweezers.
    4. Perform an "Overwrite Format" of the SD card using SD Card Formatter; Do not "quick format."
    5. Flash card using Balena Etcher directly with the zipped img file, this is intuitive:
    • Select the archive
    • Select the SD card
    • Flash and wait for verification
  1. Replace card making sure it's correctly inserted all the way with the brand side down
  2. Connect the hotspot to your internet router via an ethernet cable.
  3. Power on the hotspot again.

IMPORTANT: The Hotspot needs a minimum of
30 minutes to initialize correctly after an SD card flash. During this time please do not reboot, or disconnect the power or internet connections.  Bluetooth will also not show correct data during this time.

Ready to use SD cards are also available from:

This video also explains the process: RAK/MNTD. Helium Hotspot SD Card Replacement