[kaneorotar]

I updated my Kindle 3G to software version 3.4 last night and tried to install launchpad after jailbroken it. However, the 'Update Your Kindle' option remain greyed out after I put the bin file in the root folder. So I did a restart and, tada, 'UPDATE ERROR:3' and then the device stays in the 'USB Downloader' Mode with a screen showing "Your Kindle encountered an error."
In order to debrick it, I used the ATK to program the backup of mmcblk0p1 (version 3.1) and the corresponding uImage into the memory and it was able to startup again. Unfortunately, the 'Device Info' part seems to have lost during the process, resulting 'Wi-Fi MAC Address: Unavailable' and 'Serial Number: Unknown_Serial_ID'
As a result, my Kindle 3G is currently unable to scan for Wi-Fi Network or register. '411' stucks at 'Retrieving data...'
Could anyone provide any suggestion to help me solve this problem?
Thank you.

EDIT:
The problem is probably caused by flashing the kernel to 0x0 in the memory, which overwrote the device ID info part. I've managed to recover the S/N, PCB S/N and Wi-Fi MAC Address of my Kindle but still need the 'PCB CONFIG ID' of a 'B00A' Kindle (A 3G+Wi-Fi UK Model).

EDIT:
The problem is now SOLVED. After about two weeks effort, I'm alraedy desperate about the WiFi problem and decided to make one last attempt. So I copied the wifi and wifid scripts from the init.d folder to my computer and started reviewing. While nothing seems to be wrong in 'wifi', a proportion of code in the 'wifid' attracted my attention:

start)
        if ! internal_features_enabled || [ ! -f $WIFIOFF_FILE ]; then
            F=var/local/system/hid.csv ; [ -e /opt/$F -a ! -e /$F ] && cp /opt/$F /$F
            F=var/local/system/wifid.conf ; [ -e /opt/$F -a ! -s /$F ] && cp /opt/$F /$F

The file 'wifid.conf' reminded me some errors in the dumped logs and I start to wonder if it is the cause of the problem. So I went to the var folder backed up a few months ago and overwrote the existing 'wifid.conf' with the old one.
IT WORKED! The device discovered its MAC address at once and connected to the Wi-Fi hotspot is wasn't able to find.
However, during the process of registration, the familiar message prompted again: 'Your kindle is unable to connect this time...'
"OK, now maybe this is really the time to send this thing to Amazon." I thought, as my mouse pointer wandered among the backup files. Then a file called 'reginfo' came into view. It's in the var/local/java/prefs directory and the content seems to be some encrypted string. What's special about it is that there's no such file on my kindle. Therefore, without hoping much to happen, I copied it to the device and guess what? The device name changed immediately and I was able to connect to Whispernet again!

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OK, here's the short version of the complete process:

1. Flash the 3.4-with-jb-devkey rootfs and kernel into your kindle with ATK or k3flasher.

2. Put the usbnetwork folder (usbnet) into the storage.

3. Connect via ssh and use 'idme' command to write correct serial number, MAC address and pcb serial number into the device.

4. Copy /var/local/system/wifid.conf and /var/local/java/prefs/reginfo form your backed up files to the device and overwrite the current content.

3. Restart and everything should be working.

P.S.:
1. The device S/N and Wi-Fi Mac address can be obtained from Amazon customer service.
2. The PCB S/N is printed on a tag on the back of the PCB board which will be visible if you take the back panel off.
3. 'wifid.conf' seems to be a dynamically generated file and it is possible to solve the WiFi problem by simply deleting it. (Not tested, and prefer not to test)