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# The Raspberry Pi that booted perfectly and refused to tell anyone
- URL: https://sudoreboot.me/pi-wifi-empty-profile/
- Published: 2026-10-26T12:00:00.000Z
- Updated: 2026-10-30T15:47:16.000Z
- Description: An SD card autopsy, a clock six hours slow, and a Wi-Fi profile that was exactly zero bytes long.
- Author: Jon
- Tags: Fails, raspberry-pi, debugging

A Raspberry Pi Zero W had been humming along for ages. Then I moved it into a nice new case, and it went silent: no ping, no SSH, missing from the router's device list, solid green LED. Everything about it screamed dead SD card. Everything about it was lying.

## Autopsy on another machine

With the Pi powered off, the card went into a USB reader on a laptop. Both partitions mounted cleanly, which already ruled out the most common way these things die. Then the timestamps started talking:

- Files under `/var/lib/systemd/timers/` showed daily jobs running *after* the outage. So Linux had booted and kept on running.
- The Pi Zero has no real-time clock. Its last write was about six hours behind the real time it was unplugged, which means it never once reached a time server. The patient was alive, just completely offline.

## The smoking gun

```
$ ls -l /etc/netplan/
-rw------- 1 root root 0 ... 90-NM-....yaml
```

The Wi-Fi profile was a **zero-byte file**, and NetworkManager had no other saved connection to fall back on. Most likely, power got cut while that file was being rewritten, leaving it empty. The first-boot setup only writes network settings once, so every boot after that cheerfully came up with no network at all.

And that solid green LED? Red herring. On a Zero, the activity LED stays lit when the system is up and idle.

## The fix

Still on the laptop, I wrote a fresh NetworkManager keyfile into `/etc/NetworkManager/system-connections/` (owned by root, mode 600) and moved the empty file aside rather than deleting it. Back in the Pi, it was on the network about 80 seconds after power-on, like nothing ever happened.

> Small Pis on SD cards hate having the power yanked. `sudo poweroff` first, then unplug.