[Upgrading, Modifying and Unlocking] felixdd:
Teddyking: that is unfortunate, as I think I figured out how to convert to English finally.

So ferryboat and I have been working on this for a while. From what I understand, he managed to find an English G810 to dump the ROM. He then flashed it using TeddyKing's method, and it successfully converted his device to English.

The key difference is that he flashed it by putting the phone into bootloader mode manually -- turning it off completely, then turning it on with the voice recording button depressed.

Then ferryboat send me the ROM dump, and I tried it using Terryking's method and using Activesync to initiate bootloader. No dice.

Then I noticed that the ROM dump is identical in size to the English ROM downloaded from Toshiba.jp -- the same one that Teddyking said only activated the English keyboard, but did not change the language.

So then I started mucking around. I executed Toshiba's Chinese and English ROM and extracted ALL the files from each package. Then I ran the Chinese update package, and replaced ALL the files extracted by the Chinese package with the ones from the English package (*.BIN, and *.mbn). At this point I wasn't even sure if it was relevant, as the mbn files were all of equal sizes between the two language packages. As expected, the device was still in Chinese after this flash.

Then what I did was I copied all the files from the English package into \windows\temp, and copied in the English Flash.bin with the changed ROM ID. I then ran the "Device Software Update Utility.exe" that can only be seen if you extract the big package and look into the "\windows\temp" directory. This worked, and my device is completely in English

From what I understood of Teddyking's instruction, what he proposed was if your device was, say, in Traditional Chinese, you have to download both the Chinese and the English packages from Toshiba.jp, extract the Flash.bin from both packages, then replace the first two lines of hex of the English Flash.bin with the Chinese Flash.bin. Then, you run the CHINESE installation package, replace the Flash.bin in \windows\temp\ with your patched English Flash.bin. That didn't work for me. And from my experience, if you run the English Installation package, it won't work even if you replace the Flash.bin with a patched one -- I have no idea why.

At this point, I'm not sure what made it work -- whether it was because I flashed it twice, because I flashed it in bootloader mode, or because I flashed it using the extracted "Device Software Update Utility.exe". In any case, this is what I propose for changing the language version for Chinese.

1) Go to http://www.toshiba.co.jp/product/etsg/cmt/english/asian/g810/g810_rom.htm and download the English ROM package, as well as the ROM package that corresponds to your particular device version (e.g. if your device is from Hong Kong, download the first one).

2) Navigate to \windows\temp and leave that window open

3) Run the package that corresponds to your device. Don't connect your device to the computer.

4) Look at the windows in \windows\temp. A bunch of new files should have popped up. Copy Flash.BIN and put it somewhere safe

5) The program will give an error message. That's OK because all you wanted was the Flash.BIN from the package.

6) Run the English Package. Don't connect your device to the computer. Copy the following files from \windows\temp\

amss.mbn

amsshd.mbn

apps.mbn

appsboot.mbn

appsboothd.mbn

appshd.mbn

Device Software Update Utility.exe

Flash.bin

oemsbl.mbn

oemsblhd.mbn

partition.mbn

pass.32

qcsbl.mbn

qcsblhd_cfgdata.mbn

test.zip

7) Open the Flash.BIN of both packages using a hex editor of your choice. UltraEdit is a good one and it's free

8) Copy the first two lines of hex from the Chinese Flash.bin and paste it onto the first two lines of the English Flash.bin. The first two lines identifies the Flash.bin, so you're basically making the English Flash.bin have the identifying information of the Chinese one.

9) Remember the list of files you copied from the English build? Copy everything except "Device Software Update Utility.exe" into \windows\temp. By now the Flash.bin you placed into the \windows\temp should have been patched with the Chinese ROM's first two lines of ID data.

10) Turn your device on in bootloader mode: hold the voice record key while powering on the device, and keep the two buttons held until the number pad is shown. Activate bootloader mode, connect your device to the computer, and run "Device Software Update Utility.exe"

If my gut is right, this should work. If it works, please post here to have leave feedback so that we know this is the right method.

If the device is still in Chinese, report your findings, then run it again! If it works the second time, report it here. This way, we know whether it's running the "Device Software Update Utility.exe" that does the trick, or whether it's flashing it multiple times :P