SonyEricsson k800i firmware update/restore

The firmware update with XS++ gave me some problems at first. This document described the process of updating the k800i firmware and restore the file system after it became corrupt. This corruption was probably due to the use of the USB file transfer mode and not properly closing the file system. Note that the procedure described in here erases all the user data from your phone, including the installed applications and user data. So make sure you back-up important data! (of course the original SE games and applications will be restored).

The Basics:
Start XS++ and use the USB cable that came with your phone. Press "connect" in XS++ and while pressing the "C"-key on your phone connect the USB cable to your phone. Release the "C"-key after XS++ report that it is ready.

First thing XS++ asked was to update the EROM to CID version 52. The original version was 49. I thought it would be a good idea to update but beware that you cannot revert back to a previous CID! This also means that it is not possible to install main firmware for the old CID code. In hindsight I would not have changed the CED version because the original firmware could therefore not be restored.

Several attempts to flash the phone with only the main firmware or the file system with different revisions failed and I kept getting stuck with the "backlight problem"; once the backlight turned off, it did not come on after a key-press (only after a period of approx. 15 seconds but only if the keyboard or joystick kept untouched). This is quite annoying and I really didnít want this. So in the end I decided to flash both the main firmware and file system. In the progress reverting back to my original R1ED001 revision of the software.

The files were downloaded from the Top Sony site ( thank you guys!!). In the downloads are I found the proper files:

  • K800_R1ED001_MAIN_GENERIC_WI_RED52.mbn
  • K800_R1ED001_FS_VFE_LIVE_1_RED52.fbn

After flashing the phone with these two files, I found that after turning on the phone I got an error about the file. The result was that an icon was missing in the menu and I was not able to make video calls any more. Furthermore, I got stuck with some pre-programmed internet and WAP accounts for Belgium while I live in the Netherlands...

To solve these two problems I had to install a custom pack (also available from the download are at Top Sony). The original custom pack was at revision R14A but this file was not available so I decided to move to a higher revision. The file I ended up with was:


Fortunately XS++ keeps a log of everything that it reports and I therefore could find the original CDA code.

I found the original k800 menu in the download area with file name:

After a new (complete) programming of the flash with the main firmware, the file system and the custom pack (including the correct menu) everything seemed to work. This file gave me back all my menus and whatís more, I also didnít have any locked accounts for the internet access.

You can also put the menu file directly in the correct directory with the file option in XS++. The correct path for the menu file is:

<XS++ directory>\own_custpack\tpa\preset\system\menu

Finally, I found that I was not able to install .jad files. This turned out to be a problem of having the correct cerificate. I found the Thawte certificate including the .xml file ( necessary to install the certificate on the internet (sorry, I canít remember where exactly) but for future reference I include it in this document).


<?xml version="1.0" encoding="UTF-8" ?>
These two files can be included in the custom pack but fortunately XS++ has an option to put files into the file system. The correct path for the certificate is:

<XS++ directory>\own_custpack\tpa\preset\custom

and the two files:


Note that this only installs only one certificate. If you need additional certificates some changes to the .xml file are probably needed but I havenít looked into that until now. Maybe Iíll follow up on that in the future. After installing this certificate my phone works as it should and I am a happy guy again :)

Hopes this helps some of you guys that might be struggling with the same problems.

Best regards,