Download the update from google website: Rename the file you just downloaded to update.zip Copy the file update.zip to the root of your micro sd card. Now turn off your phone and turn it back on while holding the home key. When you see a triangle with a exclamation sign and a phone, slide open your keyboard and press ALT-L to display the menu and then ALT-S to start the update process. Wait for the update to finish. If prompted, press Home + Back to restart your phone. Wait a little bit more and done! why i can't do this? it still says thatE: Can't Open /sdcard/update.zip thought i already got the RC19+28 zip file and renamed it as update.zip i formatted my sdcard is this have effect? like i need to make a specific folder so the G1 can detect it? PLEASE HELP coz my G1 phone ain't got any apps even the messaging,calculator etc..