This is a detailed guide on how to update your Xperia X10a/i to 2.1.I will also add how to root your device after you have flashed your device. I would like to note i do not know if this will work on the Xperia X10 mini/pro so if try this with your mini its at your own risk. Also you will loose all apps, text and (phone numbers not stored on your sim) anything not on the sd card. So i would back up your text you can use SMS Backup & Restore by Ritesh Sahu. Whats required. 1. Flash Tool Part1 and part2 *(You must download both before extracting also extract both in separate folders.) Part 1:Multiupload.com - upload your files to multiple file hosting sites! Part 2:Multiupload.com - upload your files to multiple file hosting sites! 2. SEUS (Sonny Ericsson Update Service) and PC Companion.Once installed run both (When you run SEUS make sure you install the drives ALSO AT THE END IF IT SAYS YOU ARE UP TO DATE DO NOT HIT INSTALL) SEUS PC Companion Flashing Guide 1. Plug Xperia X10 into your computer and start SEUS and when it comes down to the last step DO NOT HIT INSTALL hit cancel then exit (KEEP PHONE PLUGGED IN you should see a constant green led this means your in flash mode) 2. Open Part1 and click on the X10flash.bat file (READ ALL THE TEXT) then input the following. a.Y (YES) If your going from 1.6 to 2.1 select the following 4. for X10i Users 5. for X10a Users (If your down grading then select appropriate firmware for your device) d.Y (You must select Y if your are going from 1.6 to 2.1) f. Select 1-4 (This will depend on your computers operating system so select accordingly). 3. It will search for your device once found it will begin flashing this will take a while (About 3 minutes).Once it is done press any key the X10flash.bat file will close now disconnect your X10. 4. Turn device on (hold down power button till X10 vibrates then release) you should see the Sony Ericsson logo followed buy a camera with a blue arrow.Then wait (About 2-3 minutes) Eventually your X10 will boot once it has you will go through a setup. Additional If you have an X10a then you will have the Rogers logo on load up which annoyed me (longer boot time).Also you will not have the option to change from 3g to 2g in the setting you will have to do it manually by dialing *#*#4636#*#*. You can also change your 2.1 Firmware to another that will have the 3g to 2g option and no Rogers logo.By doing the following. Switching between 2.1 Firmware Guide (for X10a) NOTE This will only work for those on 2.1 thats why you must do it after being on 2.1.You will not loose any data you've already acquired apps,phone numbers and text. 1. Plug Xperia X10a into your computer and start SEUS and when it comes down to the last step DO NOT HIT INSTALL hit cancel then exit (KEEP PHONE PLUGGED IN you should see a constant green led this means your in flash mode) 2. Open Part2 and click on the X10flash.bat file then input the following. a. Y (YES) b. 1 c. 3 (America Generic) d. N f. Select 1-4 (This will depend on your computers operating system so select accordingly). 3. It will search for your device once found it will begin flashing this will take a while (About 3 minutes).Once it is done press any key the X10flash.bat file will close now disconnect your X10. 4. Turn device on (hold down power button till X10 vibrates the release) you should see the Sony Ericsson logo followed buy a camera with a blue arrow.Then wait (About 2-3 minutes) Eventually your X10 will boot once it has you will go through a setup. Note This will not work if flashing from 1.6 to 2.1 it will still come out as a Rogers. Thats it for flashing hope this helps. I will post a guide to root your 2.1 in the next post. Hellsrage619 I would like to thank BluechipJ who compiled all of these flashing firmwares into 2 files. If you want subscribe to his youtube channel http://www.youtube.com/user/BluechipJ EDIT:Ill be adding some new stuff to this thread. PLEASE READ EVERYTHING BEFORE STARTING!! 1. Is a way to back up your current 2.1 firmware so you can try different version/ROMs and still be able to go back to a factory 2.1 firmware. 2. Ill be posting a link to my new favorite custom ROM made by X10iUser called "Eminence" as well as a simplified guide for those who arent to tech savvy. How to Back Up and Restore 2.1 Firmwares/ROMs Guide Whats needed? 1. Your phone will need to be rooted you can do so by following the guide below this post (post #2 in this thread).And its unrootable should you need repair they'll never know you rooted.Follow the guide as you will aslod need busy box which can be found in the market. 2. xRecovery download it here xRecovery 3. Astro file manager this can be found by going into the market and searching Atsro file manager (its free) just download it. How to install and Back up. 1. Connect phone to pc drop the xRecovery .apk file into your phones folder. 2. Disconnect phone open up Astro scroll down till you see the xRecovery .apk file click on it.Then select Open App Manager then hit install. 3. Open xRecovery hit install if it was done correctly then you should see those the things down bellow the install button know have green check marks on them. If it was done wrong then you will see they have a red thing over them which means it didn't install. Now when you do this make sure your not connected to your computer or charger that will cause it not to install. 4. Once installed if you want to backup your current firmware then turn your phone off then turn it back on and once you see the sony ericsson logo start hitting the back button and eventually a menu should appear. 4a. This is how you use the menu use the volume buttons to scroll down/UP and the home button to select and the back button to go back. 5. Scroll down and select backup and restore then hit back up and wait till its done once done hit reboot. 6. If you want to be safe (i recommend this) do the following plug your phone into your pc go into your phone and scroll down till you see the xRecovery folder click on it click on back up know take the folder and copy and save it somewhere on you pc.That folder is the back up of you phones system you just made. Thats it for backing up. How to install custom ROM/Restore. 1. Connect your phone to the pc open up the phone folder scroll down till you see the xRecovery folder (If you don't see the folder their simply follow the guide above and make a back up of your system and the folder will be their then just get rid of the back up in their) then click on it. 2. Get your custom ROM like the one by X10iUser which i will recommend to every one which can be downloaded here [Rom] X10 Eminence [For xRecovery] scroll down below the pics and use download link 1 its the fastest. Then extract it to your desktop. Or you can use you back up folder if you want to restore back to another version. 3. Once the xRecovery folder is open click on the back up folder then put you ROM/back up folder in it make sure its the only folder their if you have your back up in their just move it somewhere to your pc and save it. 4. Disconnect phone from pc turn phone off the turn it on and once the sony ericsson logo start hitting the back button till the xRecovery menu appears. 5. Once in the xRecovery menu select back up and restore then hit restore and wait once done hit reboot and done. NOTE: You will loose everything if installing a new ROM so i would recommend writing down what apps you have and download SMS Back up and Restore by Ritesh Sahu to save text messages and also back up your contacts to your sim ALL BEFORE DOING THIS once done installing your new ROM simply download SMS Back up and Restore again and restore your texts. I would like to thank X10iUser for taking his personal time to make the ROM "Eminence" If you would like to thank him for his work (please do)go to his thread and thank him in his first post - [Rom] X10 Eminence [For xRecovery] I would also like to thank zdzihu from xda-developers for xRecovery.