# Unbricking fails due to "protocol error"

Source: https://forum.modalai.com/topic/604/unbricking-fails-due-to-protocol-error
Category: Flight Core and Legacy VOXL (https://forum.modalai.com/category/9/flight-core-and-legacy-voxl)
Tags: voxl
Posted: 2021-12-12 05:56:46 UTC by Nirge
Replies: 2 · Views: 1229

## Nirge · 2021-12-12 05:56:46 UTC

Hi, 
I have bricked a voxl in dev, trying to restore using the debug expansion, but the process fails:
```
~/Downloads/modalai-3-1-0$ sudo ./install.sh 
[INFO] adb installed
[INFO] fastboot installed

This process will completely wipe your VOXL
Would you like to preserve the /data/ partition which contains
things like calibration, wifi config, and docker images
To preserve files in /data/ answer Y
To wipe /data/ for a full factory flash answer N

Enter Y or N: 
n
[INFO] Rebooting into fastboot...
error: no devices/emulators found
[INFO] Waiting for fastboot...
[INFO] Waiting for fastboot...
[INFO] Waiting for fastboot...
[INFO] Waiting for fastboot...
target reported max download size of 536870912 bytes
sending 'aboot' (494 KB)...
OKAY [  0.047s]
writing 'aboot'...
OKAY [  0.444s]
finished. total time: 0.492s
target reported max download size of 536870912 bytes
sending 'boot' (56066 KB)...
OKAY [  2.140s]
writing 'boot'...
OKAY [  0.745s]
finished. total time: 2.885s
target reported max download size of 536870912 bytes
erasing 'system'...
OKAY [  0.004s]
sending sparse 'system' 1/3 (523027 KB)...
FAILED (data write failure (Protocol error))
finished. total time: 9.678s

```
Would appreciate any insights and help I can get.

## Reply by Chad Sweet (ModalAI staff) · 2021-12-12 06:12:45 UTC

Are you flipping the fastboot switch back? Your symptom is consistent with leaving the fastboot switch engaged instead of setting it back to normal after a few seconds

Might be worth watching the tutorial [here](https://docs.modalai.com/unbrick-voxl/#video-tutorial) if you're unsure

## Reply by Nirge · 2021-12-12 07:58:51 UTC

Missed that part, thank you, it seems to do the trick.