> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zerokeyusb.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Troubleshooting

> Recommended steps to diagnose and fix common issues with ZeroKeyUSB.

> Follow the sections in order — many issues are resolved after completing the previous steps.

## Before You Begin

1. Ensure the device is receiving stable power through the USB-C connection.
2. Confirm that you are using the **original factory firmware** (updates are rarely needed).
3. Note any on-screen error messages and recent configuration changes.
4. If possible, back up your credentials via the **local web manager** before making changes.

***

## Quick Symptom & Solution Table

| Symptom                                  | Possible Cause                                        | Recommended Action                                                                             |
| ---------------------------------------- | ----------------------------------------------------- | ---------------------------------------------------------------------------------------------- |
| Device does not power on                 | USB cable or port not supplying power                 | Try a different USB-C cable or port; avoid USB hubs; connect directly to a PC or power bank    |
| OLED screen stays blank                  | Display initialization delay or EEPROM not responding | Wait 5 seconds after connection; if persistent, reconnect or check solder joints on the EEPROM |
| Touch buttons unresponsive               | TS06 controller not detected or miscalibrated         | Clean the golden pads and reconnect; if still unresponsive, perform a factory reset            |
| `EEPROM ERROR` or `IV MISSING` on screen | Memory communication or data corruption               | Power-cycle and retry; if persistent, contact support for inspection                           |
| Wrong PIN delays access                  | Exponential lockout triggered after failed attempts   | Wait for the countdown to complete and retry with the correct PIN                              |
| TOTP shows `REQTIME`                     | Time not synchronized with host                       | Use the web manager and press **Sync Time** before generating codes                            |

***

## Step-by-Step Procedures

### 1. Safe Restart

* Unplug ZeroKeyUSB.
* Wait about **5 seconds**.
* Reconnect to a USB power source (PC or phone).\
  The splash screen should appear within 3–5 seconds.

### 2. Reset Touch Controller

1. Disconnect and reconnect the device.
2. Wait until the **ZeroKeyUSB** logo appears.
3. Tap each golden pad to confirm all five respond.\
   If touch remains unresponsive, perform a **factory reset** to recalibrate automatically.

### 3. Firmware Flash (development units only)

> ⚠️ Production devices are resin-encapsulated and cannot be reflashed by the user.\
> This section applies **only to pre-production boards**.

1. Quickly reconnect the USB cable twice within one second to enter bootloader mode.
2. Copy the firmware `.uf2` file to the drive named **ZEROBOOT**.
3. Wait for the file transfer to complete, then reconnect normally.
4. Verify the firmware version under **Menu → Settings → About**.

### 4. Factory Reset and Reconfiguration

* Export credentials via the web manager (**Backup → Export**).
* Hold the **center touch pad** for about 10 seconds until the confirmation countdown appears.
* The process erases all memory, including credentials, PIN signature, and IV.
* After restart, re-import your backup or run the first-time setup again.

***

## Collecting Data for Support

* Connect the device and open the **Serial Monitor** at **115200 bps** to capture log output.
* Take photos of any on-screen errors.
* Note the **serial number** (`SN ZK-XXXXXXXX`) and **firmware version** from **Menu → Settings → About**.

***

## Contacting Support

If problems persist:

* Submit a support ticket at [zerokeyusb.com/support](https://zerokeyusb.com/support) including:
  * Device serial number
  * Firmware version
  * Screenshots or photos of the issue
  * Steps you’ve already tried
* Our team will reply within **24 business hours** with further guidance.

> ⚠️ **Do not attempt to open or reflash a sealed device.**\
> Doing so will destroy the waterproof encapsulation and void warranty.

***

<Note>
  This guide covers user-level diagnostics.\
  For factory calibration or advanced debugging, contact authorized service partners directly.
</Note>