Update: Though this guide is written for updating to RC29, it should work for any official update. We have tested it up to RC33.
If you’re constantly glancing at your G1 to check if T-Mobile has graced your handset with the oh-so-slow-to-roll-out RC29 update (“By November 11th”? Pah!), you might be glad to find out that there’s now a way to expedite the process. All you need is a computer, internet connection, a way to transfer the firmware to your Micro SD card and half a brain.
Mandatory warning: Updating firmware can be a delicate procedure, so continue at your own risk. Always back up everything. Unless you’re able to check the hash or otherwise verify a firmware’s source, downloading it is your own risk and not the responsibility of anyone else. Whenever possible, download it directly from Google (as you will in this tutorial). Also make sure that your battery is charged so as to keep it from fizzling out mid-update, and that you don’t have the G1 hooked up to your computer while updating.
2. Rename it from signed-PLAT-RC33-from-RC30.f06aa9b3.zip to update.zip, and place it in the root of your Micro SD card. (Note: “root” folder just means the very top folder of the drive. The directory that contains all of the folders. In “C:\Program Files\Adobe”, the root folder is just C:\)
2.5. If you added the file to your microSD card by connecting the handset to your computer via USB (rather than using a microSD card reader), make sure to unplug it now. (Thanks for the tip, Cole!)
3. Turn off your G1, then turn it back on by holding the Home+End keys until you see an icon popup after the T-Mobile G1 logo.
4. From the icon screen, open the keyboard and hit Alt+L. This will display the log saying what is happening (although you can skip this step).
5. Now press Alt+S to begin the update. Remember, the update needs to be in the root of the Micro SD card and needs to be named update.zip.
6. Once it finishes, just follow the onscreen instructions and press Home+Back to finish.
7. The G1 will reboot a few times to flash different parts of the firmware.
If all went well, you should now be running the latest update, RC33. To make sure all your hard work wasn’t for nothing, hit Menu > Settings > About Phone > scroll to Build Number. You should see RC33 in there somewhere. Congrats!
Update -T-Mobiles official word on the matter:
While I understand that many of you have downloaded this update and seem to have it working, T-Mobile cannot support you in doing so. If you download and attempt to install this or any other update (regardless whether its from Google or not) to your device, and it is rendered unusable, you are out of luck. Even if we do exchange it, you will be without a device for several days (or possibly even weeks).